Lasting relief of chronic anterior knee pain in young adult after ten weekly inductive physiotherapy sessions: A case report

Abstract

BACKGROUND:

Patellofemoral pain syndrome particularly impairs quality of life in young, physically active subjects. The exact etiology remains unknown, and so this syndrome is a challenging condition to treat. Some patients continue to experience pain and dysfunction after receiving one or more guidelines-compliant conservative treatments. Reducing the likelihood of patellofemoral pain syndrome is an important way of preventing the onset of debilitating anterior knee pain at all ages of life.

CASE:

A 24-year-old sportswoman with a 15-month history of anterior knee pain and failure of previous guidelines-compliant treatments. We treated this patient with techniques derived from the paradigm of inductive physiotherapy, in which tone disorders with a central origin may contribute to musculoskeletal disorders. One distinctive feature of inductive physiotherapy relates to the fact that the painful area is not manipulated directly.

RESULTS:

The effects of physiotherapy were evaluated after ten weekly sessions and then 15 months later. The changes in the visual analogue pain scale score and the Knee Lequesne Index were clinically significant. We also observed an unexpected reduction in the static varus misalignment.

CONCLUSION:

This case could pave the way to an innovative neurological approach to the management of patellofemoral pain syndrome in the young adult.

Keywords

Musculoskeletal disorders patellofemoral pain syndrome varus misalignment

1. Introduction

Anterior knee pain may be related to a wide variety of conditions and often prompts a diagnosis of patellofemoral pain syndrome (PFPS). This syndrome appears to be more prevalent in adolescents and physically active young adults. Furthermore, women may be more frequently affected than men; the prevalence in 18–35 year old females is 12–13% [1]. Many researchers consider that when PFPS appears during adolescence or in the young adult, it predisposes the subject to patellofemoral arthritis – an early form of knee osteoarthritis [2].

Although there are many known intrinsic and extrinsic risk factors for PFPS, the etiology of this syndrome has yet to be characterized [3]. The complex set of symptoms and the frequent absence of a causal relationship make the condition difficult to diagnose and treat, and thus explain why a wide range of conservative treatment approaches have been considered in this context. In the absence of a gold standard, a multimodal approach for PFPS management is often recommended (quadriceps and hip strengthening exercises, biofeedback, patella taping and foot orthoses) [4]. The literature results are very heterogeneous, and the recurrence rates after physical therapy appear to be high [5]. A growing body of research now suggests that certain local pain syndromes are associated with central pain mechanisms [6]. These observations might also pave the way towards a neurological understanding of PFPS.

The purpose of the present case report (on a 24-year-old sportswoman with a 15-month history of right-side PFPS) is to contribute to the development of a neurological, non-pharmacological approach to the treatment of anterior knee pain. The patient had developed chronic anterior knee pain in the absence of any associated changes in the radiographic appearance of the knee, and the symptoms had not been relieved by previous guidelines-compliant treatments. We selected an inductive physiotherapy technique based on neuromuscular facilitation. This therapeutic paradigm targets central tone disorders that may contribute to musculoskeletal disorders [7]. The technique’s remote mode of action enabled us to treat the patient without directly manipulating the knee area (which was too painful to be handled). Futhermore, inductive physiotherapy techniques have already given positive results in similar cases [8].

2. Case description

2.1 Patient history

The patient was a 24-year-old nulliparous woman (height: 166 cm; weight: 54 kg) with an unremarkable personal and family medical history. She was highly physically active (mountain hiking, running, Nordic walking, cross-country skiing and downhill skiing) both in her leisure time and professionally because she worked as a cross-country and downhill ski instructor. For the previous 15 months, she had been suffering from right anterior knee pain.

The pain appeared suddenly after a hike in the mountains. The physician diagnosed patellar tendino-pathy and prescribed rest. The symptoms persisted and further examinations were performed. The results of standard X-rays, magnetic resonance imaging, arthrography, CT scan and clinical biochemistry tests were unremarkable. There was no patellar instability. Finally, a diagnosis of idiopathic PFPS was made. The patient then started on a course of medication (non-steroidal anti-inflammatory drugs) and 20 sessions of guidelines-compliant physical therapy (a combination of osteopathy and physiotherapy). These treatments had no effect on the symptoms; despite the cessation of sporting activities, the pain returned at the same intensity two or three days after each session. The patient also reported very occasional, low-intensity, non-bothersome pain in the left knee.

2.2 Examination

The patellar ballottement test was negative. The two knees’ active and passive ranges of joint movement were normal. Lateral movement of the patella did not reveal any laxity or retraction of the collateral ligaments. The strength levels of the hamstrings, gastrocnemius and left quadriceps (evaluated manually, according to Daniels and Worthingham’s method) were normal (5 out of 5) and that of the right quadriceps was 4 out of 5. The thigh circumference (measured with a tape measure 5 and 10 cm above the patella) was 0.5 cm smaller on the non-dominant (left) side.

At the time of the examination, the left knee was asymptomatic. The right knee pain was chronic (everyday, for 15 months). Pain (felt above and under the patella) disappeared at night but resumed as soon as the patient got up in the morning. The pain greatly affected the patient’s activities of daily living and prevented her from resuming sporting activities.

2.3 Intervention

Constraints related to the patient’s work schedule limited the treatment to 10 weekly sessions over a three-month period. Inductive physiotherapy techniques are based on a paradigm in which tone disorders (excessive residual tension in the maintenance of posture) can cause musculoskeletal disorders [7]. This can be viewed as analogous to the tension in a string of a bow: tension in the muscles involved in the static (the string) causes excessive mechanical stress on the bone and joint structures (the bow) and can potentially cause pain, tissue damage and/or misalignment. Most muscles overlap with their neighbors – constituting a “muscle chain”. Hence, a tone disorder may be present in the symptomatic area and/or further away in chain. In order to correct tone disorders in these muscle chains, some inductive physiotherapy techniques use a tool called “normalizing induction”. This tool is a neuromuscular facilitation process that seeks to trigger involuntary, uncontrollable contractions in the selected target(s). These evoked responses are be triggered by specific, remote, voluntary movements performed by the patient (referred to as inductions). As the patient maintains the induction, the induced involuntary contraction progressively exhausts itself. It is postulated that the evoked response and its reduction reflects an initial exacerbation and then normalization of tone disorders along the irradiation pathway. This normalization may have an analgesic effect.

In the present case, two target zones were selected: the painful knee area and the lumbopelvic region. Several inductions were found to produce involuntary, uncontrollable contractions of the quadriceps, hip internal rotators, hip abductor, hip adductor and paravertebral lumbar muscles. We consider that the target zone has been affected when it gives an evoked response. We interpret the decrease with further maintenance of the induction as a concomitant normalisation of muscle tension, indicating that the manoeuvre can be terminated. At each session, we noted the amplitude of the response to each induction. The amplitude decreased from one session to another, even though the inductions were identical; we interpret this as the delayed (and thus possibly longer lasting) normalisation of muscle tension. Each session lasted for between 30 and 60 minutes.

Figure 1.

(i) Active elevation and lateral rotation of the arm and (ii) active rearward pressure on the head. (i): in the supine position and with the right arm alongside the body, the patient combines elevation and maximum lateral rotation of the arm with an elbow flexion angle of about 30 ${}^{\circ}$ . The practitioner helps the patient to maintain an optimal amplitude by grasping the patient’s elbow. (ii): in the sitting position, with the legs held tightly together and the knees straight, the patient pushes his head backwards (with active deflexion from a flexion-extension axis passing through the apex of the thoracic kyphosis), in order to align the occiput with the scapula and sacrum. The practitioner uses a “hockey mask” grip on the patient’s face, in order to help the patient maintain the effort.

Figure 2.

(i) Active abduction and medial rotation of the left arm and (ii) active dorsiflexion of the left ankle and passive flexion of the hip (with the leg straight). (i): on the floor. During this movement, the head tends to slide to the right; the practitioner helps the patient to avoid this movement. (ii): in the supine position, with the hip flexed passively so that the knee stays locked. The patient performs active, lateral rotation of the hip (while keeping the leg straight) and flexes the toes and ankle as much as possible. The practitioner checks to ensure that ankle pronation does not occur.

Although many different techniques were applied, we describe four in particular (and the respective induced responses) because they were used in all sessions (Figs 1 and 2): (i) active elevation and lateral rotation of the right arm prompted the right knee to push against the ground, with involuntary, uncontrollable contractions of the quadriceps and the hip adductor; (ii) active rearward pressure on the head in the sitting position triggered the involuntary accentuation of lumbar lordosis; (iii) active abduction and medial rotation of the left arm induced the involuntary accentuation of the pelvic anteversion, lumbar lordosis, and medial rotation and abduction of the right thigh; and (iv) active left ankle dorsiflexion with passive hip flexion (with the leg straight) induced the involuntary contraction of the medial rotators and adductors of the right hip.

A technique introduced during the sixth session (abduction of the fifth toe in the supine position, which nevertheless affected the knee area) was discontinued because of worsened anterior knee pain in the hours following the session and which was still present at the start of the seventh session. A possible explanation is given in the Discussion section.

Table 1

Results for the pain visual analogue scale (VAS) and the Knee Lequesne Index (KLI)

	A week before	A week after	After 15 months
	the first session (T0)	the last session (T1)	(T2)
VAS for usual pain	51	12	0
VAS for squatting pain	83	13	0
VAS for running pain	65	0	0
Pain or discomfort	5 out of 8	0 out of 8	0
Walking	2 out of 8	0 out of 8	0
Activities of daily living	4 out of 8	0.5 out of 8	0
Total KLI	11 out of 24	0.5 out of 24	0 out of 24

2.4 Evaluation criteria

The following criteria were used to evaluate whether or not the treatment was successful:

•
A 0-to-100 mm VAS, to evaluate the levels of the previous week’s usual pain, pain during squatting and pain during running. A score of 0 mm corresponds to the absence of pain and a score of 100 mm corresponds to the worst imaginable pain.
•
The Knee Lequesne Index [9], to evaluate the pain’s functional impact. The index’s psychometric values have been validated and its completion time is quite short ( $<$ 5 min), which contributes greatly to its acceptability. This test was preferred to the Kujala scale for patients with patellofemoral pain because the French-language version of the latter (which would have been particularly well suited to the present case) has not been validated.

The Knee Lequesne Index includes 11 questions on three different domains: “pain or discomfort” (5 questions), “walking” (2 questions), and “activities of daily living” (4 questions). Up to 8 points can be scored in each domain. The domain scores are aggregated into an overall score that ranges from 0 to 24.

Data were recorded at three time points: a week before the first session (T0), a week after the last session (T1) and after 15 months without treatment (T2). The usual pain in the previous week was also assessed at the beginning of each session.
3. Outcomes

There were no adverse events (illness, accidents, etc.), other interventions (whether pharmacological or physiotherapeutic) or self-administered exercises performed at home during and after the treatment phase.

Table 1 reports the results on the knee pain’s intensity (according to the VAS) and functional impact (according to the Knee Lequesne Index) a week before the first session (T0), a week after the last session (T1) and after 15 months without treatment (T2) :

•
At T0, the usual pain was categorized as moderate (score between 31–69) each day and all day long, and affected the patient’s quality of life; the functional impact was categorized as very severe (score: 11–13)
•
At T1, the residual pain was very occasional and was categorized as mild (score: 1–30) and no longer impacted the patient’s quality of life (the functional impact was null; score $<$ 1).

Figure 3.
Results for the intensity of usual knee pain observed at each session. The intensity fluctuated up until the fifth session and fell to zero at the sixth session. However, the patient again complained of pain at the start of the seventh session; the pain had reappeared a few hours after the end of the sixth session. The pain was not continuously present but re-occurred on a daily basis; this was probably related to premature discontinuation of the technique (i.e. before the normalization phase had been reached). The pain level fell again from the eighth session onwards. The minimal clinically important difference (MCID, 20 mm on a 100-mm VAS in patients with patellofemoral pain) was achieved at the sixth session – even when baseline pain levels were taken into account (MCID $=$ 27 for a baseline VAS score of between 50 and 65) .

Figure 4.
Photographs showing a reduction in varus misalignment. (T0): the patient stands in a reproducible stance, with her feet together and aligned with a ground marker; (T1): after 10 treatment sessions, the legs were closer together, and the gap between the knees was smaller; (T2): after 15 months without treatment, the outcome was partially maintained.

Figure 3 summarized the intensity of usual knee pain noted at each session.

Figure 4 shows photographs of the lower limbs:

•
At T1: we observed a reduction in the static varus misalignment, with (i) a decrease in the gap between the knee and the calves and (ii) the appearance of intermalleolar contact.
•
At T2: after 15 months without treatment and the full resumption of leisure- and work-related sporting activities, the knee realignment was partially maintained.

4. Discussion

The treatment goals had been achieved: normal quality of life and the resumption of leisure and work-related sporting activities. This case highlights the lasting relief of chronic anterior knee pain in a young adult after ten weekly physiotherapy sessions. These results were obtained through a remote mechanism, i.e. in the absence of direct manipulation of the painful knee. The pain level fell from the fifth session onwards. This observation is frequent in routine practice: the pain level does not decrease immediately but appears to be subject to a cumulative/threshold effect. Reappearance of pain between the sixth and the seventh sessions might have been due to the premature discontinuation of treatment, before the concomitant extinction of evoked response (medial femoral rotation) associated with the newly introduced technique (abduction of the fifth toe in the supine position). Pain and functional impact were again assessed after 15 months without treatment. On the day of the assessment, the patient was completely pain-free, whereas the usual pain at T1 was rated at 12 out of 100. It appeared that the treatment had a delayed effect. This delay is often observed in routine practice but we do not have a robust explanation for this phenomenon. In the time interval between T1 and T2, the patient had not received any other treatments. The patient stated that she has been pain-free since the end of the treatment and has been able to resume all her activities.

The knee realignment was unexpected because this young adult’s bones had matured several years previously. Despite the absence of radiologic data, we consider that this case report contributes useful scientific knowledge. Indeed, the concomitant decreases in symptom intensity and varus misalignment argue in favor of a common, central origin for these musculoskeletal disorders.

The outcome of the present neurorehabilitation paradigm fits with literature data on central mechanisms in several local pain syndromes (probably related to cortical plasticity) [6]. With regard to the paradigm of inductive physiotherapy, some of the chronic pain may have a central (rather than a local) origin. However, in cases treated with inductive physiotherapy, local pain is explained by a muscle tone disorder and not by central sensitization. In both cases, one observes long-lasting pain with a putative central origin (the same as in varus misalignment) for which a specific pain reduction tool is required (normalizing induction).

These results also agree with the recent literature data on concepts in physiotherapy (in which some of the effects of manual physiotherapy on musculoskeletal disorders, pain levels and motor control are due to neuroplasticity) [10].

The above-mentioned concomitance also suggests that misalignment was a risk factor for PFPS in this patient. Although only one study had established a causal relationship between varus misalignment and anterior knee pain [11], other researchers have suggested that misalignment may contribute to the pathogenesis of PFPS [12]. If this hypothesis is true, treatment strategies that seek to reduce misalignment would decrease mechanical stress and thus relieve knee pain. Quadriceps strengthening has been explored as a means of reducing misalignment in patients with medial knee osteoarthritis; however, there was no significant improvement (vs. controls) in knee pain and function after 12 weeks of treatment [13]. Another randomized, controlled trial showed that hip strengthening relieved symptoms after 12 weeks (although the longer-term effects were not evaluated) but did not modify the misalignment [14].

In the present case, there does not appear to be a link between tissue damage and knee pain. This observation converges with the results of some population-based studies in which clinical pain was poorly correlated with radiographic severity. Despite the bones’ maturity, the pathogenic process was still reversible – probably because the bone and joint structures were intact (i.e. in the absence of tissue damage). Destieux et al. have reported a case of reduction of varus misalignment and concomitant knee pain relief in an adolescent treated with inductive physiotherapy techniques (59 sessions over a 26-month period): there was no tissue damage and the realignment was fully maintained 3 years after the last session [8]. Hence, bone maturity may not be a barrier to recovery of normal posture, provided that tissue damage does not make the process irreversible. By generating excessive mechanical stress, varus misalignment may lead to cartilage damage, which may then progress to medial patellofemoral osteoarthritis. This mechanical risk factor also acts as a risk factor for medial tibiofemoral osteoarthritis: it doubles the risk of onset and quadruples the risk of progression [15].

Further research is needed to evaluate the effectiveness of inductive physiotherapy techniques in a wide range of patients with PFPS. If strong evidence of effectiveness is found, these techniques could contribute to the neurological management of knee pain in young adults with PFPS.

Conflict of interest

None of the authors has any conflicts of interest to declare.

Footnotes

Acknowledgments

We thank Guillaume Rebert for provision of clinical data (with the patient’s consent).

References

Roush

Curtis Bay

. Prevalence of anterior knee pain in 18–35 year-old females. Int J Sports Phys Ther. 2012; 7(4): 396-401.

Utting

Davies

Newman

. Is anterior knee pain a predisposing factor to patellofemoral osteoarthritis? Knee. 2005; 12(5): 362-365.

McCarthy

Strickland

. Patellofemoral pain: an update on diagnostic and treatment options. Curr Rev Musculoskelet Med. 2013; 6: 188-194.

Bolgla

Boling

. An update for the conservative management of patellofemoral pain syndrome: a systematic review of the literature from 2000 to 2010. Int J Sports Phys Ther. 2011; 6(2): 112-25.

Pappas

Wong-Tom

. Prospective Predictors of Patellofemoral Pain Syndrome: A Systematic Review With Meta-analysis. Sports Health. 2012; 4(2): 115-20.

Lee

Nassikas

Clauw

. The role of the central nervous system in the generation and maintenance of chronic pain in rheumatoid arthritis, osteoarthritis and fibromyalgia. Arthritis Res Ther. 2011; 13(2): 211.

Nisand

. Le travail à distance: Explication et illustration d’un principe de base de la Reconstruction Posturale à travers deux exemples de pathologies courantes. Kinesither Rev. 2009; 96: 23-7.

Destieux

Gaudreault

Isner-Horobetti

M-E

, et al. Use of Postural Reconstruction® physiotherapy to treat an adolescent with asymmetric bilateral genu varum and idiopathic scoliosis. Ann of Phys and Rehabil Med. 2013; 56(4): 312-26.

Veenhof

Bijlsma

van den Ende

, et al. Psychometric Evaluation of Osteoarthritis Questionnaires: A Systematic Review of the Literature. Arthritis & Rheumatism. 2006; 55(3): 480-92.

10.

Werstine

Chesworth

. IFOMPT 2012: a rendez-vous of hands and minds. J Orthop Sports Phys Ther. 2012; 42(10): A1-A83.

11.

Lun

Meeuwisse

Stergiou

Stefanyshyn

. Relation between running injury and static lower limb alignment in recreational runners. Br J Sports Med. 2004; 38(5): 576-80.

12.

Teitge

Torga Spak

. Skeletal Malalignment and Anterior Knee Pain: Rationale, Diagnosis, and Management in Anterior Knee Pain and Patellar Instability. Second Edition. Springer. 2011, pp. 209-221.

13.

Lim

Hinman

Wrigley

, et al. Does knee malalignment mediate the effects of quadriceps strengthening on knee adduction moment, pain, and function in medial knee osteoarthritis? A randomized controlled trial. Arthritis Rheum. 2008; 59: 943-51.

14.

Bennell

Hunt

Wrigley

, et al. Hip strengthening reduces symptoms but not knee load in people with medial knee osteoarthritis and varus malalignment: a randomised controlled trial. Osteoarthritis Cartilage. 2010; 18: 621-8.

15.

Barrios

Higginson

Royer

, et al. Static and dynamic correlates of the knee adduction moment in healthy knees ranging from normal to varus-aligned. Clin Biomech (Bristol, Avon). 2009; 24(10): 850-4.