Proximal and distal kinematics in female runners with patellofemoral pain

Background

Female runners have a high incidence of developing patellofemoral pain. Abnormal mechanics are thought to be an important contributing factor to patellofemoral pain. However, the contribution of abnormal trunk, hip, and foot mechanics to the development of patellofemoral pain within this cohort remains elusive. Therefore the aim of this study was to determine if significant differences during running exist in hip, trunk and foot kinematics between females with and without patellofemoral pain.

Methods

32 female runners (16 patellofemoral pain, 16 healthy control) participated in this study. All individuals underwent an instrumented gait analysis. Between-group comparisons were made for hip adduction, hip internal rotation, contra-lateral pelvic drop, contra-lateral trunk lean, rearfoot eversion, tibial internal rotation, as well as forefoot dorsiflexion and abduction

Findings

The patellofemoral pain group had significantly greater peak hip adduction and hip internal rotation. No differences in contra-lateral pelvic drop were found. A trend towards reduced contra-lateral trunk lean was found in the patellofemoral pain group. No significant differences were found in any of the rearfoot or forefoot variables but significantly greater shank internal rotation was found in the patellofemoral pain group.

Interpretation

We found greater hip adduction, hip internal rotation and shank internal rotation in female runners with patellofemoral pain. We also found less contra-lateral trunk lean in the patellofemoral pain group. This may be a potential compensatory mechanism for the poor hip control seen. Rehabilitation programs that correct abnormal hip and shank kinematics are warranted in this population.     

Lower extremity kinetics during stair ambulation in patients with and without patellofemoral pain

Objective. To compare lower extremity kinetics during stair ascent and descent in subjects with and without patellofemoral pain.

Design. A cross-sectional study utilizing a control group.

Background. The patellofemoral joint reaction force (the resultant force between the quadriceps muscle force and patellar ligament force) increases with quadriceps force and knee flexion angle. Consequently, patients with patellofemoral pain may employ compensatory strategies to minimize pain and reduce patellofemoral joint reaction forces during activity.

Methods. 10 individuals with a diagnosis of patellofemoral pain and 10 individuals without pain participated. Subject groups were matched on sex, age, height, and body mass. Anthropometric data, three dimensional kinematics, and ground reaction forces were used to calculate lower extremity sagittal plane moments (inverse dynamics) while subjects ascended and descended stairs at a self-selected pace. Differences in kinetic variables between groups were assessed using 2×2 (group × stair condition) analysis of variance.

Results. Subjects with patellofemoral pain had decreased peak knee extensor moments during stair ascent and descent. There were no group differences in peak hip, ankle, or support moments, however, subjects with patellofemoral pain had decreased cadence (descent) compared to controls.

Conclusion. Subjects with patellofemoral pain had reduced peak knee extensor moments, suggesting that quadriceps avoidance was employed to reduce patellofemoral joint reaction forces. The lack of group differences in peak moments at the hip and ankle suggests that secondary compensation did not occur exclusively at the hip or ankle in this group of subjects with patellofemoral pain.Relevance statement

Because stair ambulation is often used to evaluate the reproducibility of symptoms and to identify abnormal movement patterns indicative of patellofemoral pain, knowledge of lower extremity mechanics during stair negotiation is necessary to better characterize compensatory behavior in this population.     

Mirror gait retraining for the treatment of patellofemoral pain in female runners

Background

Abnormal hip mechanics are often implicated in female runners with patellofemoral pain. We sought to evaluate a simple gait retraining technique, using a full-length mirror, in female runners with patellofemoral pain and abnormal hip mechanics. Transfer of the new motor skill to the untrained tasks of single leg squat and step descent was also evaluated.

Methods

Ten female runners with patellofemoral pain completed 8 sessions of mirror and verbal feedback on their lower extremity alignment during treadmill running. During the last 4 sessions, mirror and verbal feedback were progressively removed. Hip mechanics were assessed during running gait, a single leg squat and a step descent, both pre- and post-retraining. Subjects returned to their normal running routines and analyses were repeated at 1-month and 3-month post-retraining. Data were analyzed via repeated measures analysis of variance.

Findings

Subjects reduced peaks of hip adduction, contralateral pelvic drop, and hip abduction moment during running (P < 0.05, effect size = 0.69–2.91). Skill transfer to single leg squatting and step descent was noted (P < 0.05, effect size = 0.91–1.35). At 1 and 3 months post retraining, most mechanics were maintained in the absence of continued feedback. Subjects reported improvements in pain and function (P < 0.05, effect size = 3.81–7.61) and maintained through 3 months post retraining.

Interpretation

Mirror gait retraining was effective in improving mechanics and measures of pain and function. Skill transfer to the untrained tasks of squatting and step descent indicated that a higher level of motor learning had occurred. Extended follow-up is needed to determine the long term efficacy of this treatment.     

Coupling angle variability in healthy and patellofemoral pain runners

Background

Patellofemoral pain is hypothesized to result in less joint coordination variability. The ability to relate coordination variability to patellofemoral pain pathology could have many clinical uses; however, evidence to support its clinical application is lacking. The aim was to determine if vector coding's coupling angle variability, as a measure of joint coordination variability, was less for runners with patellofemoral pain than healthy controls as is commonly postulated.

Methods

Nineteen female recreational runners with patellofemoral pain and eleven healthy controls performed a treadmill acclimation protocol then ran at a self-selected pace for 15 min. 3-D kinematics, force plate kinetics, knee pain and rating of perceived exertion were recorded each minute. Data were selected for the: pain group at the highest pain reached (pain ≥ 3/10) in a non-exerted state (exertion < 14/20), and; non-exerted healthy group from the eleventh minute. Coupling angle variability was calculated over several portions of the stride for six knee–ankle combinations during five non-consecutive strides.

Findings

46 of 48 coupling angle variability measures were greater for the pain group, with 7 significantly greater (P < .05).

Interpretation

These findings oppose the theory that less coupling angle variability is indicative of a pathological coordinate state during running. Greater coupling angle variability may be characteristic of patellofemoral pain in female treadmill running when a larger threshold of pain is reached than previously observed. A predictable and directional response of coupling angle variability measures in relation to knee pathology is not yet clear and requires further investigation prior to considerations for clinical utility.     

Hamstring length in patellofemoral pain syndrome

Objectives

To investigate whether there was a difference in hamstring length between patients with patellofemoral pain syndrome and healthy asymptomatic controls aged 18 to 35 years.

Design

A cross-sectional observational study measuring hamstring length in patients and asymptomatic controls.

Setting

Hospital physiotherapy department.

Participants

Two groups were tested; one group diagnosed with patellofemoral pain syndrome (mean age 27 years, n = 11, six males, five females) and one group of asymptomatic controls (mean age 25 years, n = 25, 13 males, 12 females).

Main outcome measures

Hamstring length was evaluated using the passive knee extension method to measure popliteal angle.

Results

The mean (standard deviation) values for hamstring length were 145.6 (8.7)° for patients with patellofemoral pain syndrome and 153.7 (10.1)° for the asymptomatic controls. The mean (95% confidence interval) difference between the groups was 8.0 (0.8 to 15.1)°, and analysis with a t-test revealed that this was statistically significant (P < 0.05).

Conclusions

This study found that patients with patellofemoral pain had shorter hamstring muscles than asymptomatic controls. It is not clear whether this is a cause or effect of the condition. Further research is suggested to study how hamstring length changes with rehabilitation, and the relationship with pain.     

Moderate-heeled shoes and knee joint torques relevant to the development and progression of knee osteoarthritis

OBJECTIVE: To determine if women's dress shoes with heels of just 1.5 in (3.8 cm) in height increases knee joint torques, which are thought to be relevant to the development and/or progression of knee osteoarthritis (OA) in both the medial and patellofemoral compartments. DESIGN: Randomized controlled trial. SETTING: A 3-dimensional motion analysis gait laboratory. PARTICIPANTS: Twenty-nine healthy young women (age, 26.7+/-5.0 y) and 20 healthy elderly adult women (age, 75.3+/-6.5 y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Peak external varus knee torque in early and late stance and prolongation of flexor knee torque in early stance. Three-dimensional data on lower-extremity torques and motion were collected during walking while (1) wearing shoes with 1.5-in high heels and (2) wearing control shoes without any additional heel. Data were plotted and qualitatively compared; major peak values and timing were statistically compared between the 2 conditions using paired t tests. RESULTS: Peak knee varus torque during late stance was statistically significantly greater with the heeled shoes than with the controls, with increases of 14% in the young women and 9% in the elderly women. With the heeled shoes, the early stance phase knee flexor torque was significantly prolonged, by 19% in the young women and by 14% in elderly women. Also, the peak flexor torque was 7% higher with the heeled shoe in the elderly women. CONCLUSIONS: Even shoes with moderately high heels (1.5 in) significantly increase knee torques thought to be relevant in the development and/or progression of knee OA. Women, particularly those who already have knee OA, should be advised against wearing these types of shoes.     

Ankle positioning and knee perturbation affect temporal recruitment of the vasti muscles in people with patellofemoral pain

Objectives

To compare the temporal recruitment of the vastus medialis obliquus (VMO) and vastus lateralis (VL) during voluntary ankle movements and perturbed standing in people with patellofemoral pain, and to determine the effects of different reflex and voluntary postural exercise tasks on VMO facilitation.

Design

Repeated-measures design.

Participants

Twenty-three subjects with patellofemoral pain.

Interventions

Quadriceps reflex contraction in response to postero-anterior knee perturbations was measured with three crural muscle contraction conditions and three postural exercises (semi-squatting, tip-toeing and heel standing).

Main outcome measures

The electromyographic (EMG) onset time of the VMO and VL during each task was measured and compared across the different tasks.

Results

The mean EMG onset time of the VMO was later than that of the VL in the voluntary tasks such as tip-toeing (VMO 95.3 ms vs VL 36.4 ms, mean difference 58.9 ms, 95% confidence interval −33.7 to 151.5 ms), whereas earlier VMO activation was found in the perturbation tests such as toe standing (VMO 17.6 ms vs VL 22.9 ms, mean difference −5.3 ms, 95% confidence interval −25.3 to 14.7 ms).

Conclusion

These findings suggest the potential benefits of unexpected perturbation activities for facilitating VMO activation. The clinical applications of perturbation tasks in rehabilitation exercise programmes and the underlying mechanisms warrant further investigation.     

Quadriceps muscle activity in women runners with and without patellofemoral pain syndrome.

The purpose of this study was to determine whether there was a difference in the electromyographic (EMG) patterns of the quadriceps muscles in women runners diagnosed with patellofemoral pain syndrome (PFPS) compared to the quadriceps activity of women runners free of knee pain and with normal lower extremity alignment. Linear envelope EMGs from vastus medialis, vastus lateralis, and rectus femoris, together with a footswitch signal, were recorded as each subject ran on a treadmill at 80% of their normal running pace and at 12km/h. Each stride period was normalized to 100%, then the linear envelopes for ten trials were ensemble averaged to achieve a mean ensemble for each muscle from each subject. Subsequently, the ensembles for each subject were normalized by dividing by the maximum EMG per cycle; they were then averaged across subjects to obtain the grand mean ensembles of each muscle for each group. Comparisons between the experimental and control groups at both speeds showed that nowhere during the stride cycle did the mean EMG levels of the two groups differ by more than two standard deviations. It was concluded that any changes in the running pattern of the runners with patellofemoral pain syndrome could not be detected by changes in the EMG patterns.     

Electric muscle stimulation of the quadriceps in the treatment of patellofemoral pain

OBJECTIVE: To compare a commercially available electric muscle stimulation regimen with a novel form of stimulation for the rehabilitation of the quadriceps muscle, in patients with patellofemoral pain syndrome. DESIGN: Double-blinded randomized trial with a parallel control group and stratified randomization. SETTING: Home-based rehabilitation program assessed in research center. PARTICIPANTS: Eighty patients (47 women, 33 men) with patellofemoral pain syndrome. INTERVENTIONS: One group (EMPI) received 1 uniform constant frequency component of 35Hz. The other (EXPER) group received an experimental form of stimulation that contained 5 simultaneously delivered frequency components of 125, 83, 50, 2.5, and 2Hz. Stimulation was applied to the quadriceps muscles of the affected leg for 1 hour daily for 6 weeks, a total of 42 treatments. MAIN OUTCOME MEASURES: Lower-limb isometric and isokinetic torque, quadriceps fatigue, knee flexion, patellar pain, a step test, quadriceps cross-sectional area, and Kujala patellofemoral score for pain before and after treatment. RESULTS: Seventy-four patients (43 women, 31 men) completed the trial. Patients in both groups showed significant improvements in all outcomes (P<.05). No significant differences existed between the 2 stimulators in any outcome (P>.05) except for quadriceps cross-sectional area (P=.023). CONCLUSIONS: One form of stimulation was just as efficacious as the other in improving subjective and objective measures.     

Outcomes of a weight-bearing rehabilitation program for patients diagnosed with patellofemoral pain syndrome

OBJECTIVE: To determine the effects of a weight-bearing rehabilitation program on quadriceps and gluteus medius electromyographic activity, pain, and function in subjects diagnosed with patellofemoral pain syndrome (PFPS). DESIGN: Pretest and posttest 6-week intervention study. SETTING: Musculoskeletal research laboratory. PARTICIPANTS: Fourteen subjects diagnosed with PFPS and 14 healthy control subjects volunteered to participate in this study. No subjects withdrew from the study because of adverse effects. INTERVENTION: Subjects diagnosed with PFPS participated in a 6-week rehabilitation program. The rehabilitation program consisted of weight-bearing exercises that focused on strengthening the quadriceps and hip abductor musculature. MAIN OUTCOME MEASURES: Electromyographic onsets of the vastus medialis oblique (VMO) and vastus lateralis and onset and duration of the gluteus medius were collected during a stair-stepping task that was performed during the pretest and posttest. A visual analog scale (VAS) and Functional Index Questionnaire (FIQ) were administered at pretest and posttest and each week of the intervention. RESULTS: Vastus lateralis and VMO onset timing differences (vastus lateralis electromyographic onset minus VMO electromyographic onset) and VAS and FIQ scores significantly improved for patients diagnosed with PFPS. Vastus lateralis and VMO onset timing in the PFPS group were significantly different from those in the control group at baseline and were not significantly different from the control group after the intervention. We did not find differences in gluteus medius onsets or duration of activity. CONCLUSIONS: Subjects diagnosed with PFPS responded favorably and quickly to a therapeutic exercise program that incorporated quadriceps and hip musculature strengthening. The efficacy of the therapeutic exercise program used in this study should be further investigated in a larger subject population.     

Running gait biomechanics in female runners with sacroiliac joint pain

[Purpose] To identify running gait biomechanics associated with sacroiliac (SI) joint pain in female runners compared to healthy controls. [Participants and Methods] In this case-control study, treadmill running gait biomechanics of female runners diagnosed SI joint pain, (by ultrasound-guided diagnostic SI joint injection and/or ≥2 positive SI physical exam maneuvers) were compared with age, height, mass, and BMI matched healthy female runners. Sagittal and coronal plane treadmill running video angles were measured and compared. [Results] Eighteen female runners with SI pain, and 63 matched controls, were analyzed. There was no difference in age, height, mass, or BMI between groups. At the point of initial contact, runners with SI joint pain demonstrated less knee flexion, greater tibial overstride, and greater ankle dorsiflexion, compared to controls. In midstance, runners with SI pain had greater contralateral pelvic drop compared to controls. For unilateral SI joint pain cases (N=15), greater contralateral pelvic drop was observed when loading their affected side compared to the unaffected side. [Conclusion] Female runners with SI joint pain demonstrated greater contralateral pelvic drop during midstance phase; along with less knee flexion, greater “tibial overstride”, and greater ankle dorsiflexion at initial contact compared to controls.     

The effect of medial patellar taping on pain, strength and neuromuscular recruitment in subjects with and without patellofemoral pain

Objectives

Patellar taping is used by clinicians to reduce pain, increase strength and enhance neuromuscular recruitment in patients with patellofemoral pain. This study explored the effect of medial patellar taping on these parameters in physically active subjects with and without patellofemoral pain.

Study design

A placebo-controlled clinical trial with randomised interventions.

Setting

Sport Science Institute of South Africa.

Participants

Fifteen subjects with patellofemoral pain (experimental group) and 20 subjects without patellofemoral pain (healthy cohort).

Methods

Pain perception, quadriceps force output and electromyographic (EMG) data were collected during maximal quadriceps strength testing and submaximal step testing for each intervention.

Intervention

Subjects were tested during three different knee taping conditions: (1) no tape; (2) placebo tape; and (3) medial tape, in a randomised order.

Main outcome measures

Visual analogue scale (VAS), isokinetic and isometric force output, and EMG analysis.

Results

Medial patellar tape did not result in a significant reduction in pain during the step testing (step-up) in the group with patellofemoral pain (no tape condition: mean VAS 1.0, 95% confidence interval 0.30-1.70; taped condition: mean VAS 1.07, 95% confidence interval 0.22-1.91) or an increase in quadriceps force output. However, there was a significant decrease in EMG activity of the vastus medialis oblique in both groups during the closed chain step test (e.g. group with patellofemoral pain, no tape condition: mean 77%, 95% confidence interval 62-92%; taped condition: mean 64%, 95% confidence interval 53-75%, P < 0.05).

Conclusion

Although taping did not reduce pain in the patellofemoral pain group, it did enhance the efficiency of the vastus medialus oblique. Future studies should determine whether there are clinical benefits to these findings.     

Training program and additional electric muscle stimulation for patellofemoral pain syndrome: a pilot study

Bily W, Trimmel L, Mödlin M, Kaider A, Kern H. Training program and additional electric muscle stimulation for patellofemoral pain syndrome: a pilot study.

Objectives

To evaluate the beneficial effect of training in patients with patellofemoral pain syndrome (PFPS) and influence of additional electric muscle stimulation (EMS) of the knee extensor muscles.

Design

A randomized clinical trial.

Setting

Supervised physiotherapy (PT) training and home-based EMS.

Participants

Patients (N=38; 14 men, 24 women) with bilateral PFPS.

Interventions

One group (PT) received supervised PT training for 12 weeks. The other received PT and EMS. The stimulation protocol was applied to the knee extensors for 20 minutes, 2 times daily, 5 times a week for 12 weeks at 40Hz, with a pulse duration of .26ms, at 5 seconds on and 10 seconds off. Maximal tolerable stimulation intensity was up to 80mA.

Main Outcome Measures

Patellofemoral pain assessment with visual analog scale during activities of daily life, Kujala patellofemoral score, and isometric strength measurement before and after 12 weeks treatment as well as after 1 year.

Results

Thirty-six patients completed the 12-week follow-up. There was a statistically significant reduction of pain in both groups (PT group, P=.003; PT and EMS group, P<.001) and significant improvement of the Kujala score in both groups (PT group, P<.001; PT and EMS group, P<.001) after 12 weeks of treatment with improvement of function and reduction of pain at the 1-year follow-up. The difference between the 2 treatment groups was statistically not significant. We could not measure any significant change in isometric knee extensor strength in either group.

Conclusions

A supervised PT program can reduce pain and improve function in patients with PFPS. We did not detect a significant additional effect of EMS with the protocol described previously.     

Effects of laterally wedged insoles on knee and subtalar joint moments

OBJECTIVE: To assess the biomechanic effects of wearing a lateral wedge on the knee joint varus moment during gait in elders with and without knee osteoarthritis (OA). DESIGN: Crossover design whereby subjects walked under 2 different insole conditions: a 0 degrees control wedge and a 6 degrees lateral wedge. SETTING: A gait laboratory with 3-dimensional motion analysis and force platform equipment. PARTICIPANTS: Thirteen healthy subjects and 13 knee patients with OA. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Frontal plane angles and moments at the knee and subtalar joints, ground reaction forces, and center of pressure. Moments were derived by using a 3-dimensional inverse dynamics model of the lower extremity. RESULTS: The 6 degrees lateral wedge significantly reduced knee joint varus moment and increased subtalar joint valgus moment in both groups when compared with no wedge. All patients had a greater knee joint varus moment with a similar subtalar joint valgus moment compared with the people without OA. There were diverse, sometimes reversed effects with the insole among the patients. CONCLUSIONS: The 6 degrees lateral wedge did not consistently reduce the knee joint varus moment in patients with knee OA. The biomechanic indications and limitations of laterally wedged insoles should be confirmed by a larger study.     

The incidence and potential pathomechanics of patellofemoral pain in female athletes

Background

The aims of this study were to determine the prevalence and incidence of patellofemoral pain (PFP) in young female athletes and prospectively evaluate measures of frontal plane knee loading during landing to determine their relationship to development of PFP. We hypothesized that increased dynamic knee abduction measured during preseason biomechanical testing would be increased in those who developed PFP relative to teammates who did not develop PFP.

Methods

Middle and high school female athletes (n = 240) were evaluated by a physician for PFP and for landing biomechanics prior to their basketball season. The athletes were monitored for athletic exposures and PFP injury during their competitive seasons.

Findings

At the beginning of the season, the point prevalence of PFP was 16.3 per 100 athletes. The cumulative incidence risk and rate for the development of new unilateral PFP was 9.66 per 100 athletes and 1.09 per 1000 athletic exposures, respectively. All new PFPs developed in middle school athletes who demonstrated mean International Knee Documentation Committee score of 85.6 ± 7.7 at diagnosis. The new PFP group demonstrated increased knee abduction moments at initial contact (95% CI: 0.32 to 4.62 N m) on the most-symptomatic limb and maximum (95% CI: 1.3 to 10.1 N m; P = 0.02) on the least-symptomatic (or no symptoms) limb relative to the matched control limbs. Knee abduction moments remained increased in the new PFP group when normalized to body mass (P < 0.05).

Interpretation

The increased knee abduction landing mechanics in the new PFP group indicate that frontal plane loads contribute to increased incidence of PFP.     

An examination of the relationship between dynamic knee joint stiffness and gait pattern of children with cerebral palsy

Dynamic joint stiffness represents the resistance that a joint opposes to an applied moment. Stiffness arises in conditions of joint laxity, instability and increased co-contraction and is commonly utilized as a means to stabilize the joint. The knee joint seems to be crucial for determining the walking pattern. The aim of this study was to investigate the association between the gait pattern, globally quantified by the Gait Profile Score (GPS), which indicates the ‘quality’ of a particular walking strategy, and knee dynamic joint stiffness (Kk) in children with diplegia. Kk is expressed by plotting the values of the knee flexion-extension moment versus the knee flexion-extension angle during weight acceptance. In this interval, the linear regression was fitted. The angular coefficient of the linear regression corresponded to the joint stiffness index. Sixty-one children with diplegia and 18 healthy individuals took part in this study. From their gait analysis data, the GPS (with its Gait Variable Scores-GVSs) and the Kk were calculated. Data showed that GPS (p = 2.73 × 10^?21) and GVSs values for the patients with diplegia were higher in comparison to healthy controls. The Kk values for patients were not statistically different from those of controls. The correlation between Kk and GPS did not show the presence of any significant relationship (r = ?0.04; p > 0.05). Thus, the functional limitation in diplegic children does not seems to be strictly related to Kk.     

A comparison of shoulder joint forces during ambulation with crutches versus a walker in persons with incomplete spinal cord injury

OBJECTIVE: To compare 3-dimensional (3D) shoulder joint reaction forces and stride characteristics during bilateral forearm crutches and front-wheeled walker ambulation in persons with incomplete spinal cord injury (SCI). DESIGN: Cross-sectional cohort study. SETTING: Biomechanics laboratory. PARTICIPANTS: Fourteen adult volunteers with incomplete SCI recruited from outpatient rehabilitation hospital services. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Peak force, rate of loading, and force-time integral were compared for each component of the net 3D shoulder joint reaction force during ambulation with crutches and a walker. Stride characteristics were also compared between assistive device conditions. RESULTS: The largest weight-bearing force was superiorly directed, followed by the posterior force. The superior joint force demonstrated a significantly higher peak and rate of loading during crutch walking (48.9N and 311.6N/s, respectively, vs 45.3N and 199.8N/s, respectively). The largest non-weight-bearing force was inferiorly directed with a significantly greater peak occurring during crutch ambulation (43.2N vs 23.6N during walker gait). Walking velocity and cadence were similar; however, stride length was significantly greater during crutch walking (62% vs 58% of normal). CONCLUSIONS: Shoulder joint forces during assisted ambulation were large. Crutch use increased the superior force but did not increase walking velocity.     

Lumbopelvic manipulation in patients with patellofemoral pain syndrome

Objectives:

A recent clinical prediction rule (CPR) identified characteristics that may predict an immediate reduction in pain following lumbopelvic manipulation in patients with patellofemoral pain syndrome. The purpose of this single-arm cohort study was to replicate the proposed CPR in a different population and investigate changes in self-reported pain, hip range of motion, strength, and function immediately following lumbopelvic manipulation.

Methods:

Forty-four subjects (63·6% female; mean age 27·4 years) met inclusion criteria. Hip internal rotation range of motion, lower extremity strength using a handheld dynamometer, and single/triple hop tests were assessed prior to and immediately following a spinal manipulation. A global rating of change questionnaire was administered after testing and telephonically at 1 week. Paired t-tests compared pre- and post-manipulation range of motion, strength, and hop test limb symmetry indices (α = 0·05).

Results:

Fifty-seven percent of subjects had a successful outcome measured by the numerical pain rating scale immediately following manipulation. Twenty-five of subjects experienced a successful outcome as measured by the global rating of change questionnaire at 1 week. No single individual or combination of predictor variables predicted a positive outcome immediately following the lumbopelvic manipulation (+likelihood ratio 0·7 with three of five predictor variables present). Statistically significant differences (P<0·05) were found in hip extension and abduction strength and hip internal rotation symmetry post-manipulation, but do not appear to be clinically meaningful.

Discussion:

The previously identified CPR was not able to be replicated and no clinically meaningful changes in range of motion, strength, or function were apparent. Future research should focus on a comprehensive impairment-based treatment approach in patients with patellofemoral pain syndrome.     

Lumbopelvic manipulation in patients with patellofemoral pain syndrome

Abstract

Objectives: A recent clinical prediction rule (CPR) identified characteristics that may predict an immediate reduction in pain following lumbopelvic manipulation in patients with patellofemoral pain syndrome. The purpose of this single-arm cohort study was to replicate the proposed CPR in a different population and investigate changes in self-reported pain, hip range of motion, strength, and function immediately following lumbopelvic manipulation.

Methods: Forty-four subjects (63·6% female; mean age 27·4 years) met inclusion criteria. Hip internal rotation range of motion, lower extremity strength using a handheld dynamometer, and single/triple hop tests were assessed prior to and immediately following a spinal manipulation. A global rating of change questionnaire was administered after testing and telephonically at 1 week. Paired t-tests compared pre- and post-manipulation range of motion, strength, and hop test limb symmetry indices (α?=?0·05).

Results: Fifty-seven percent of subjects had a successful outcome measured by the numerical pain rating scale immediately following manipulation. Twenty-five of subjects experienced a successful outcome as measured by the global rating of change questionnaire at 1 week. No single individual or combination of predictor variables predicted a positive outcome immediately following the lumbopelvic manipulation (+likelihood ratio 0·7 with three of five predictor variables present). Statistically significant differences (P<0·05) were found in hip extension and abduction strength and hip internal rotation symmetry post-manipulation, but do not appear to be clinically meaningful.

Discussion: The previously identified CPR was not able to be replicated and no clinically meaningful changes in range of motion, strength, or function were apparent. Future research should focus on a comprehensive impairment-based treatment approach in patients with patellofemoral pain syndrome.