The American Journal of Sports Medicine

Background: Most posterior cruciate ligament reconstruction techniques use a tibial bone tunnel, which results in an acute bend in the graft as it passes over the posterior portion of the tibial plateau.

Hypothesis: The tibial inlay technique will result in lower graft pretensions, less laxity, and less stretch-out after cyclic loading.

Study Design: Controlled laboratory study.

Methods: Graft pretensions necessary to restore normal laxity at 90° of knee flexion (laxity match pretension) and anteroposterior laxities at five knee flexion angles were recorded in 12 fresh-frozen knee specimens with bone-patellar tendon-bone posterior cruciate ligament graft reconstructions using both techniques and two femoral tunnel positions.

Results: When the graft was placed in a central femoral tunnel, the tibial tunnel reconstruction required an average 15.6 N greater laxity match pretension than the tibial inlay reconstruction. There were no significant differences in mean knee laxities between the tibial tunnel and tibial inlay techniques at any knee flexion angle; both reconstruction techniques restored mean knee laxity to within 1.6 mm of intact knee values over the entire flexion range.

Conclusions: There was no important advantage of one technique over the other with respect to the biomechanical parameters measured.

Background: Initial nonoperative treatment of pain at the Achilles tendon, often referred to as “tendinitis,” is not always successful.

Hypothesis: Surgical treatment is effective for patients with insertional tendinitis unrelieved by nonoperative measures.

Study Design: Retrospective cohort study.

Methods: Thirty-five patients (41 feet) who had painful Achilles tendon syndrome unrelieved by 6 months of nonoperative measures were treated surgically. The technique consisted of a single incision along the lateral border of the Achilles tendon. The dissection exposed the retrocalcaneal bursa and fat pad, which were completely excised along with any scarred and thickened paratenon. A partial calcaneal exostectomy of the tubercle was performed.

Results: At a minimum follow-up of 20 months (average, 39), the patients' pain scores (rated from 0 to 6) improved from 4.7 (SD, 1.1) preoperatively to 1.5 (SD, 1.3); 90% had complete or significant relief of symptoms, 10% felt improved, and none felt unchanged or worse.

Conclusions: Surgical treatment of chronic Achilles tendon pain with resection of the prominent tuberosity, complete debridement of the bursa, excision of thickened, scarred paratenon, and removal of accessible calcific deposits within the tendon is an effective treatment.

Background: In recent years, various investigators have begun using lasers in the treatment of shoulder instability.

Hypothesis: Arthroscopic laser-assisted capsular shift is an effective treatment for patients with multidirectional shoulder instability.

Study Design: Retrospective cohort study.

Methods: We retrospectively identified 28 patients (30 shoulders) with multidirectional shoulder instability who were unresponsive to nonoperative management and who had undergone the laser-assisted capsular shift procedure. Twenty-five patients (27 shoulders) with an average follow-up of 28 months were available for review. All patients underwent a physical examination and completed a general questionnaire; the University of California, Los Angeles, shoulder rating scale; the Western Ontario Shoulder Instability Index; and the Short-Form 36 quality of life index.

Results: In 22 shoulders, results of the procedure were considered a success because the patients had no recurrent symptoms and at latest follow-up had required no further operative intervention. In five shoulders, results were considered a failure because of recurrent pain or instability and the need for an open capsular shift procedure. With recurrent instability as a measure of failure, the overall success rate was 81.5%.

Conclusions: Our results with laser-assisted capsular shift are comparable with the results of other open and arthroscopic techniques in relieving pain and returning athletes to their premorbid function.

Background: Research has shown that variations in femoral intercondylar notch morphometry may be a predisposing factor for noncontact anterior cruciate ligament injury.

Hypothesis: There are anatomic differences in the anterior cruciate ligament and femoral notch between men and women.

Study Design: Descriptive anatomic study.

Methods: Using magnetic resonance imaging, we performed a three-dimensional analysis of the femoral intercondylar notch morphometry to look for differences in femoral notch and anterior cruciate ligament volumes between men and women. Axial plane magnetic resonance imaging scans were performed on 96 knees in 48 asymptomatic subjects. Digital measurements were taken of femoral notch area, anterior cruciate ligament area, notch width, and bicondylar width, within defined parameters of the femoral notch. The notch and anterior cruciate ligament volumes were then calculated. Analysis of variance was performed using sex, height, and weight as covariates.

Results: The volume of the femoral notch was found to be statistically smaller in women compared with men; this difference was primarily related to height. A similar relationship was found for anterior cruciate ligament volume. A statistically significant correlation was found between femoral notch volume and anterior cruciate ligament volume; patients with smaller notches also had smaller anterior cruciate ligaments.

Conclusions: Our results suggest that there is a difference in femoral notch and anterior cruciate ligament volume between men and women, which, in turn, is related to differences in height and weight.

Background: Despite the high prevalence of residual quadriceps muscle weakness after anterior cruciate ligament reconstruction, specific predictive factors have not been identified.

Hypothesis: Electromyographic analysis is a better predictor of residual muscle weakness than is preoperative strength.

Study Design: Prospective cohort study.

Methods: The quadriceps muscle strength of 37 patients (25 men, 12 women) was measured before reconstruction and 5 weeks and 6 months after surgery. Quadriceps surface electromyographic signals were recorded during all of the strength tests. Integrated electromyographic analysis and median frequency measurements were computed as deficits on the involved side. Patients also performed a single-legged hop test at the 6-month follow-up examination.

Results: The patients had significantly lower strength, integrated electromyographic analysis, and median frequency measurements on the involved side at all three time intervals. The best predictor of the quadriceps muscle strength deficit at 6 months was the combination of the preoperative median frequency deficit and the 5-week postoperative strength deficit. The best predictor of the hop test deficit at 6 months was the combination of preoperative deficits in integrated electromyographic analysis and median frequency. Conclusion: Preoperative electromyographic indices of quadriceps muscle function and early postoperative

strength were predictive of residual weakness and impaired function 6 months after reconstruction.

Background: Unsatisfactory long-term results have been reported after use of a Broström repair for patients with chronic ankle ligament insufficiency.

Hypothesis: Repair or reconstruction of both the anterior talofibular and calcaneofibular ligaments is essential for normal kinematics of the ankle-hindfoot.

Study Design: Case series.

Methods: Thirteen patients with chronic instability of the ankle were found at operation to have injuries of both the anterior talofibular and calcaneofibular ligaments, with a lack of healthy ligament margins suitable for suturing. Reconstruction of the ligaments was performed with bone-patellar tendon graft. The score devised by Good et al. was used to assess the patients' clinical condition before the operation and at final follow-up.

Results: Before the operation, six patients had a grade 3 clinical condition and seven had a grade 4 condition. At a mean follow-up of 26.5 months, all patients had a grade 1 condition. The average talar tilt of the patients was improved from 18.4° ± 5.5° to 4.9° ± 2.6°, and the average anterior drawer sign was improved from 9.1 ± 2.6 mm to 5.8 ± 1.6 mm.

Conclusion: In cases of combined injuries, short-term results of reconstruction of the anterior talofibular and calcaneofibular ligaments using bone-split patellar tendon graft were good, with a low frequency of complications.

Background: Increased external rotation and decreased internal rotation have been noted to occur progressively in the throwing shoulder of baseball pitchers.

Hypothesis: Proximal remodeling of the humerus contributes to the rotational asymmetry between shoulders in pitchers.

Study Design: Descriptive anatomic study.

Methods: Both shoulders of 19 male college baseball pitchers were evaluated and retroversion of the humerus calculated by using the technique of Söderlund et al. Measurements were taken of passive glenohumeral external rotation at 0° and 90° of abduction and internal rotation at 90° of abduction under a 3.5-kg load. Subjects completed a questionnaire on the amount and duration of overhead throwing performed during the ages 8 through 16 years.

Results: All of the subjects had greater external rotation at 0° and 90° of abduction, decreased internal rotation at 90° of abduction, and greater retroversion of the humerus in their dominant compared with nondominant shoulders. A significant difference was found between dominant and nondominant external rotation at 0° and 90° of abduction, internal rotation at 90° of abduction, and retroversion of the humerus. In the dominant arm, there was a significant correlation between retroversion of the humerus and external rotation at 0° and 90° of abduction. There was also a significant correlation between the side-to-side difference in retroversion of the humerus compared with the side-to-side difference in external rotation at 90° of abduction.

Conclusions: Rotational changes in the throwing shoulder are due to bony as well as soft tissue adaptations.

Background: Previous studies have documented changes in musculature, bony anatomy, and glenohumeral rotation in the dominant shoulder of baseball players.

Hypothesis: In a group of asymptomatic college baseball players the total range of motion in the dominant and nondominant shoulders will be similar. Any measured increase in external rotation and decrease in internal rotation occurring between the two sides will be consistent and directly correlate with an increased angle of humeral retroversion in the dominant extremity.

Study Design: Descriptive anatomic study.

Methods: Fifty-four asymptomatic college baseball players were examined. Standard measurements of glenohumeral range of motion were made and humeral retroversion was determined radiologically.

Results: Total rotational motion, measured at 90° of glenohumeral abduction, was 159.5° for the dominant shoulders and 157.8° for the nondominant shoulders. Mean differences in external and internal rotation in the dominant versus nondominant extremities were 9.7° and 8.2°, respectively. Humeral retroversion measured 36.6° ± 9.8° in the dominant and 26° ± 9.4° in the nondominant extremity. The mean difference in retroversion correlated significantly by Pearson's product moment with the difference in external (P = 0.001) and internal ( P = 0.003) rotation measurements.

Conclusions: There is a pattern of increased external rotation and decreased internal rotation in the dominant extremity that significantly correlates with an increase in humeral retroversion. The loss of internal rotation and gains in external rotation may be more strongly related to adaptive changes in proximal humeral anatomy than to changes in the soft tissues.

Background: Injury of the anterior cruciate ligament changes the kinematics of the knee joint. In studies of cadaveric knees, investigators have examined the effect of anterior cruciate ligament reconstruction on knee kinematics, but the effect on dynamic knee motion is not known.

Hypothesis: Reconstruction of the anterior cruciate ligament restores knee kinematics to normal.

Study Design: Prospective cohort study.

Methods: Nine patients were examined preoperatively and 1 year after reconstruction. Continuous radiostereometric exposures were performed at a speed of two to four exposures per second while the patients ascended an 8-cm high platform. Tibial rotation and tibial and femoral translation were measured with radiostereometric analysis.

Results: Tibial rotation and tibial and femoral translation were not significantly different after anterior cruciate ligament reconstruction compared with preoperative measurements. A radiostereometric evaluation of anterior knee laxity revealed restoration to within 1 mm of that on the uninjured side. Further evaluation of knee function using the Lysholm score, the Tegner activity level score, the International Knee Documentation Committee evaluation system score, and measurements of laxity using the KT-1000 arthrometer revealed significant improvements after reconstruction.

Conclusion: Kinematics of the anterior cruciate ligament injured knee did not change significantly after ligament reconstruction, but the functional results were satisfactory and knee laxity was diminished.

Background: Several problems have been reported with use of allogenic grafts in anterior cruciate ligament reconstruction, including local immune response to allograft tendon within the synovial fluid, delayed maturation and ligamentization, and progressive tibial tunnel enlargement.

Hypothesis: There is a correlation between the use of allograft and tibial tunnel enlargement.

Study Design: Controlled laboratory study.

Methods: Twenty healthy adult female goats underwent allograft anterior cruciate ligament reconstruction and were followed with serial radiographs at 6-week intervals. Animals were randomly chosen for sacrifice between 18 and 36 weeks for histologic assessment.

Results: Significant radiographic increases in tunnel size were noted within the first 6 weeks of healing and remained up to 36 weeks with no further remodeling noted. Histologic analysis showed progressive ligamentization of the allografts with tendon-to-tunnel wall biologic fixation with dense connective tissue. Remodeling and incorporation of the bone plug was seen in all cases. The allograft tendon underwent early fibrous attachment within the tunnel and remodeled toward ligament histologic structure. Remodeling and incorporation of the bone plug was seen by 18 weeks.

Conclusion: Tibial tunnel enlargement, consistent with that seen in humans after allograft anterior cruciate ligament reconstruction, did not appear to affect the ultimate incorporation of the allograft on a histologic level.

Background: Electromyography has been used to determine the best exercise for strengthening the supraspinatus muscle, but conflicting results have been reported. Magnetic resonance imaging T2 relaxation time appears to be more accurate in determining muscle activation.

Purpose: To determine the best exercises for strengthening the supraspinatus muscle.

Study design: Criterion standard.

Methods: Six male volunteers performed three exercises: the empty can, the full can, and horizontal abduction. Immediately before and after each exercise, magnetic resonance imaging examinations were performed and changes in relaxation time for the subscapularis, supraspinatus, infraspinatus, teres minor, and deltoid muscles were recorded.

Results: The supraspinatus muscle had the greatest change among the studied muscles in relaxation time for the empty can (10.5 ms) and full can (10.5 ms) exercises. After the horizontal abduction exercise the change in relaxation time for the supraspinatus muscle (3.6 ms) was significantly smaller than that for the posterior deltoid muscle (11.5 ms) and not significantly different from that of the other muscles studied.

Conclusion: The empty can and full can exercises were most effective in activating the supraspinatus muscle.

Background: The capsule and ligaments are generally viewed as the primary stabilizers of the glenohumeral joint, but many important activities are performed in midrange positions in which these structures are lax.

Hypothesis: In vivo, the humeral head can be centered in the glenoid, even when the shoulder is in positions in which the capsule is lax and even when the shoulder is passively positioned.

Study Design: Controlled laboratory study.

Methods: We documented the centering of the humeral head in the relaxed shoulders of six subjects using open-magnet magnetic resonance imaging scans.

Results: While these shoulders were passively placed in midrange positions (those not at the extremes of motion), the humeral head center was never more than 2.2 mm from the glenoid center (mean + 0.1 ± 1.2 mm).

Conclusions: The results suggest that mechanisms other than ligamentous restraint, such as the compressive effect of resting muscle tone into the conforming concavity of the glenoid, may be sufficient to maintain centering of the glenohumeral joint. Further exploration of these mechanisms may lead to methods other than ligament tightening or capsular shrinkage for restoration of stability to joints that are unstable in the midrange of motion.

Clinical Relevance: In that many patients with unstable shoulders demonstrate instability in midrange positions, it is hoped that further study of living shoulders will lead to a more effective understanding of the nonligament mechanisms of shoulder stability and the ways in which these stabilizing mechanisms can be restored.

Background: Chronic overload is considered the main cause of patellar tendinitis, but it has been postulated that impingement of the inferior patellar pole against the patellar tendon during knee flexion could be responsible.

Hypothesis: The role of the patellar pole in patellar tendinitis can be determined by dynamic magnetic resonance imaging.

Study Design: Case-control study.

Methods: We compared 19 knees with patellar tendinitis and 32 asymptomatic knees of age-matched subjects using an open-configuration magnetic resonance imaging system. Dynamic sagittal images were obtained from full extension to 100° of flexion with and without activation of the quadriceps muscle. The following measurements were made from the images: tendon-patella angle, anteroposterior diameter of the tendon, signal difference-to-noise ratio, the shape of the inferior patellar pole, and the location of the patellar tendon insertion.

Results: The tendon-patella angle was not significantly different between groups at any flexion angle, with or without quadriceps muscle activation. The insertion site of the patellar tendon differed significantly but not the shape of the inferior pole of the patella. The volume and the signal difference-to-noise ratio of zones of increased intratendinous signal as well as the anteroposterior diameter of the proximal patellar tendon were increased in symptomatic knees.

Conclusions: The relationship between the patella and the patellar tendon was identical in both groups; therefore, chronic overload seems to be a major cause of patellar tendinitis.

Background: A number of clinical conditions of the patellofemoral joint have been correlated with abnormal patellofemoral radiographic measurements.

Hypothesis: An abnormal anteroposterior patellar-tilt angle may be a contributing factor to pathologic conditions of the knee.

Study Design: Prospective nonrandomized clinical trial.

Methods: The anteroposterior patellar-tilt angle was measured in cadaveric knees to determine the best knee position. The radiographs of normal subjects and patients with patellar tendinitis or patellofemoral pain syndrome were examined for differences in patellar-tilt angle.

Results: Cadaveric measurements demonstrated highest intertester and intratester reliability at 30° of knee flexion and neutral femoral rotation. Intratester measurements on normal subjects exhibited high reliability, with a mean anteroposterior tilt angle of 30.8° ± 6.7°. In the patellofemoral pain group the mean anteroposterior tilt angle was 29.1° ± 8.5°; however, for patients with patellar tendinitis, it was 25.6° ± 7.0°, significantly lower than in the normal population. Furthermore, there was no difference between the angles of involved and uninvolved knees of patients with unilateral patellar tendinitis.

Conclusion: The anteroposterior patellar-tilt angle is a clinically reliable measurement of patellar tilt in the sagittal plane that can be used to study patellofemoral tilt in a variety of clinical situations. The results of this study demonstrate that patients with patellar tendinitis have abnormal patellar tilt in the sagittal plane.

Background: There are little objective data on structural changes of the chronically unstable ankle. Such knowledge could help with preoperative planning.

Hypothesis: Preoperative ankle arthroscopy provides important insights into the causes and mechanisms of ankle instability and the resulting disability.

Study Design: Case series.

Methods: From 1993 to 1999, arthroscopic examination was performed in the ankles of 148 patients with symptomatic chronic ankle instability that had lasted 6 months or more. All structural changes were recorded and compared with the clinical diagnosis.

Results: A rupture or elongation of the anterior talofibular ligament was noted in 86% of ankles, of the calcaneofibular ligament in 64%, and of the deltoid ligament in 40%. Cartilage damage was noted in 66% of ankles with lateral ligament injuries, whereas 98% of the ankles with deltoid ligament injuries had cartilage damage. Although lateral instability could be verified arthroscopically in 127 patients, medial instability was presumed clinically in 38 patients but was actually detected in 54 patients arthroscopically.

Conclusion: Preoperative ankle arthroscopy revealed an essential amount of information that would otherwise have been undetected. For instance, the ligaments showed typical abnormalities corresponding to different entities of ankle instability and different intra-articular pathologic conditions.

Background: Repair of a torn rotator cuff should have sufficient initial strength of the fixation to permit appropriate rehabilitation.

Hypothesis: Augmentation with a woven polylactic acid scaffold strengthens repairs of the rotator cuff.

Study Design: Controlled laboratory study.

Methods: In the suture-anchor model, 10 pairs of sheep infraspinatus tendons were detached and repaired to suture anchors. In half of the matched specimens, the repair was reinforced with a woven poly-lactic acid scaffold repaired with the tendon to bone. In the bone-bridge model, sutures were passed through a trough and over a bone bridge distal to the greater tuberosity; half were reinforced by the scaffold. The repairs were tested to failure with a hydraulic testing machine.

Results: The mean ultimate strength of suture-anchor repairs augmented with the scaffold (167.3 ± 53.9 N) was significantly greater than that of nonaugmented fixation (133.2 ± 38.2 N). Failure occurred when the tendon pulled through the sutures; the scaffold remained intact. Scaffold reinforcement of the bone bridge significantly increased the ultimate strength from 374.6 ± 117.6 N to 480.9 ± 89.2 N, and the scaffold remained intact in 8 of 10 specimens.

Conclusions: The scaffold significantly increased the initial strength of rotator cuff repair by approximately 25%.

Background: Patients with medial compartment osteoarthritis of the knee may be treated nonoperatively with adjustable valgus bracing.

Hypothesis: Valgus bracing reduces load on the medial compartment through the application of an external valgus moment about the knee, resulting in pain relief.

Study Design: Prospective cohort study.

Methods: Eleven patients were tested using an instrumented brace and three-dimensional gait analysis. We measured the valgus moment applied by the adjustable valgus brace and determined the compressive load in the medial compartment. We also documented the effects of increased valgus alignment of the brace and increased strap tension on load sharing. Pain and activity levels were also recorded.

Results: Pain and activity level improved in all subjects with valgus bracing. During gait, valgus bracing reduced the net varus moment about the knee by an average of 13% (7.1 N•m) and the medial compartment load at the knee by an average of 11% (114 N) in the calibrated 4° valgus brace setting. Increasing valgus alignment with the adjustable brace had a greater effect on the medial compartment load than did increasing strap tension.

Conclusion: Adjustable valgus bracing was effective in reducing medial compartment load and subsequent pain while also improving knee function in a group of patients with osteoarthritis.

Background: The results of both nonoperative and surgical treatments for lateral epicondylitis of the elbow have been inconsistent. Shock wave therapy has been shown to have a favorable short-term effect in treating this condition.

Hypothesis: Shock wave therapy is an effective treatment for patients with lateral epicondylitis of the elbow and long-term results will be as favorable as short-term ones.

Study Design: Case series.

Methods: The effect of shock wave therapy was investigated in 57 patients with lateral epicondylitis of the elbow. Forty-three patients (24 men and 19 women with an average age of 46 years) with 1 to 2 years of follow-up were included in this study. In addition, six patients were treated with a sham procedure as a control group. Each patient was treated with 1000 impulses of shock wave therapy at 14 kV to the affected elbow. A 100-point scoring system was used for evaluating pain, function, strength, and elbow range of motion.

Results: Twenty-seven elbows (61.4%) were free of complaints, 13 (29.5%) were significantly better, 3 (6.8%) were slightly better, and 1 (2.3%) was unchanged. In the control group, the results were unchanged in all six patients. There were no device-related problems and no systemic or local complications.

Conclusions: Shock wave therapy is a safe and effective modality in the treatment of patients with lateral epicondylitis of the elbow.

Background: Injuries to the ulnar collateral ligament are relatively common in throwing athletes and result from either acute traumatic or repeated valgus stress to the elbow. Avulsion fracture of the sublime tubercle of the ulna is a rarely reported site of ulnar collateral ligament injury.

Purpose: We retrospectively reviewed our cases of ulnar collateral ligament injuries to study avulsion fractures of the sublime tubercle of the ulna. Study Design: Case series.

Methods: Data, including radiographs and magnetic resonance imaging scans, were obtained by review of hospital and office records and by follow-up examination. Of 33 consecutive patients treated for ulnar collateral ligament injuries, 8 had avulsion fractures of the sublime tubercle of the ulna. All eight were male baseball players with dominant arm involvement, an average age of 16.9 years, and an average follow-up of 23.6 months.

Results: Six of eight patients had failure of nonoperative treatment and required surgical repair. Two of the six underwent ulnar collateral ligament reconstruction and four had direct repair of the sublime tubercle avulsion with bioabsorbable suture anchors. At last follow-up, all eight had returned to their preinjury level of activity. No patient had residual medial elbow pain or laxity.

Conclusions: Diagnosis of sublime tubercle avulsion fracture is made with history, physical examination, and radiographic studies. Magnetic resonance imaging can help identify an avulsion fracture not visible radio-graphically and can help determine whether direct repair or reconstruction is needed.

Background: Rupture of the distal biceps brachii tendon has most commonly been repaired by anatomic reattachment of the tendon to the radial tuberosity by a single- or two-incision approach. Researchers have studied suture anchor attachment through a single incision, but the tendon-suture interface and bone quality have not previously been analyzed.

Hypothesis: Suture anchor repair results in stiffness and tensile strength equal to that of bone-tunnel repair for biceps tendon rupture.

Study Design: Controlled laboratory study.

Methods: Twelve matched pairs of fresh-frozen cadaveric elbow specimens were used. Suture anchor and bone-tunnel tendon repairs were performed in a randomized fashion. Each specimen was loaded to tensile failure. Load-displacement graphs were generated to calculate repair stiffness, yield strength, and ultimate strength. Computed tomography bone density measurements and additional statistical analyses were then performed after grouping the specimens by mode of failure.

Results: The bone-tunnel repair was found to be significantly stiffer in all cases and to have significantly greater tensile strength than the suture anchor repair in the younger, nonosteoporotic elbows.

Conclusions: Suture anchor repairs were not as stiff or strong as bone-tunnel repairs.

Clinical Relevance: Biceps tendon surgery using the traditional two-incision technique yields a stronger and stiffer repair in the typical patient with this injury.

The patient-athlete with patellofemoral pain requires precise physical examination based on a thorough history. The nature of injury and specific physical findings, including detailed examination of the retinacular structure around the patella, will most accurately pinpoint the specific source of anterior knee pain or instability. Radiographs should include a standard 30° to 45° axial view of the patellae and a precise lateral radiograph. Nonoperative treatment is effective in most patients. Prone quadriceps muscle stretches, balanced strengthening, proprioceptive training, hip external rotator strengthening, patellar taping, orthotic devices, and effective bracing will help most patients avoid surgery. When surgery becomes necessary, indications must be specific. Lateral release is appropriate for patella tilt (abnormal rotation). Painful scar or retinaculum, neuromas, and pathologic plicae may require resection. Proximal patellar realignment may be accomplished using arthroscopic or a combined arthroscopic/mini-open approach. Symptomatic articular lesions and more profound malalignments may require medial or anteromedial tibial tubercle transfer. Clinicians should be particularly alert for symptoms of medial subluxation in postoperative patients and should use the provocative medial subluxation test followed by lateral displacement patellar bracing to confirm a diagnosis of medial patellar subluxation. This problem may be corrected in most patients using a lateral patellar tenodesis. Current thinking emphasizes precise diagnosis, rehabilitation involving the entire kinetic chain, restoration of patella homeostasis, minimal surgical intervention, and precise indications for more definitive corrective surgery.