The influence of abnormal hip mechanics on knee injury: a biomechanical perspective

The impact of quadriceps femoris strength asymmetry on functional performance at return to sport following anterior cruciate ligament reconstruction

STUDY DESIGN

Cross-sectional study.

OBJECTIVES

To investigate the impact of quadriceps femoris (QF) muscle strength asymmetry at the time of return to sport on self-reported function and functional performance of individuals following anterior cruciate ligament reconstruction (ACLR).

BACKGROUND

Evidence-based QF strength guidelines for return-to-sport decision making are lacking. Objective guidelines necessitate understanding the impact of QF strength deficits at the time of return to sport on function and performance.

METHODS

Fifty-five individuals (mean age, 17.3 years) who were cleared for return to sport following primary ACLR (ACLR group) and 35 uninjured individuals (mean age, 17.0 years) in a control group participated in the study. QF strength (maximum voluntary isometric contraction) was assessed, and the quadriceps index (QI) was calculated [(involved strength/uninvolved strength) × 100%]. The ACLR group was further subdivided into 2 groups, based on the QI: high quadriceps (QI of 90% or greater) and low quadriceps (QI of less than 85%). The International Knee Documentation Committee Subjective Knee Evaluation Form score was used to assess self-reported function, and hop tests were used to assess functional performance. Multivariate analysis of variance and hierarchical regression analyses were performed.

RESULTS

The individuals in the ACLR group were weaker, reported worse function, and performed worse on hop tests compared to those in the control group (P<.05). The low-quadriceps group demonstrated worse performance on the hop tests compared to the high-quadriceps group and the control group (P ≤.016). Hop test performance did not differ between the high-quadriceps and control groups (P ≥.14). QF strength predicted performance on the hop tests beyond graft type, presence of meniscus injury, knee pain, and knee symptoms.

CONCLUSION

At the time of return to sport, individuals post-ACLR who had weaker QF (QI of less than 85%) demonstrated decreased function, whereas those with minimal QF strength deficits (QI of 90% or greater) demonstrated functional performance similar to uninjured individuals. QF strength deficits predicted hop test performance beyond the influences of graft type, presence of meniscus injury, knee pain, and knee symptoms.

Relação entre hiperpronação subtalar e lesões do ligamento cruzado anterior do joelho: revisão de literatura

INTRODUÇÃO: A ruptura do ligamento cruzado anterior (LCA) é uma lesão severa, que resulta em instabilidade funcional e distúrbios articulares degenerativos. Fatores de risco proximais à articulação do joelho têm sido bastante enfatizados na última década, mas pouca atenção tem sido dada para os fatores de risco distais ao joelho. A hiperpronação subtalar (HS) foi sugerida por alguns autores como possível fator de risco às lesões do LCA, mas as evidências da literatura a respeito são escassas e pouco conclusivas. OBJETIVO: O propósito deste estudo foi realizar uma revisão dos estudos da literatura que avaliaram as alterações de alinhamento da articulação subtalar associadas à lesão do LCA ou associadas a outros fatores de risco conhecidos para essa lesão. MATERIAIS E MÉTODOS: Foi realizada uma busca em bases eletrônicas (PubMed, MEDLINE, COCHRANE, Web of Science, PEDro, SciELO, LILACS e EMBASE), compreendendo publicações de 1966 até 2011. RESULTADOS E DISCUSSÃO: Foram encontrados nove estudos clínicos considerados pertinentes ao tema. Desses trabalhos, quatro identificaram HS em indivíduos com lesão do LCA e um apontou correlação entre HS e outros fatores de risco para lesões do LCA. A não identificação de correlação entre essas variáveis nos demais estudos se deve, provavelmente, a diferenças metodológicas nas avaliações. Deve-se ressaltar que a natureza retrospectiva dos estudos encontrados não permite o estabelecimento de causa e consequência nesse contexto. São necessários estudos prospectivos, com mais uniformidade metodológica, para o definitivo estabelecimento da HS como efetivo fator de risco para as lesões do LCA.

The effect of hip bracing on gait in patients with medial knee osteoarthritis

Objective. Impaired hip motion has been associated with heightened medial knee joint loading in patients with knee osteoarthritis (OA). A hip external rotation strap designed to pull the femur into external rotation and abduction may serve as one protective mechanism. The primary aim of our study is to determine if the strap decreases medial knee joint loading during level walking in people with knee OA. Design. This study is a single-day repeated measures design. Methods. 15 volunteers with medial knee OA underwent motion analysis data collection during two randomly assigned walking conditions: (1) wearing the strap and (2) control (no strap). Primary outcome measures were peak pelvis, hip and knee joint motions, and torques. These outcomes were averaged across five trials for each condition. Results. Hip abduction (P < 0.01), trunk lean towards the stance limb (P = 0.04) and pelvic tilt (P = 0.02) significantly increased with the strap versus control trials. Knee adduction loading did not significantly change with the strap (P = 0.33). Conclusion. The use of the hip external rotation strap resulted in angular changes at the hip and pelvis which may be beneficial for patients with medial knee osteoarthritis.

The relationship between rearfoot, tibial and hip kinematics in individuals with patellofemoral pain syndrome

BACKGROUND

Excessive rearfoot eversion is thought to be a risk factor for patellofemoral pain syndrome development, based on theoretical rationale linking it to greater tibial internal rotation and hip adduction. This study aimed to establish the relationship of rearfoot eversion with tibial internal rotation and hip adduction during walking in individuals with and without patellofemoral pain syndrome.

METHODS

Twenty-six individuals with patellofemoral pain syndrome and 20 controls (18-35years) participated. Each underwent instrumented three-dimensional motion analysis during over-ground walking. Pearson's correlation coefficients (r) were calculated to establish the relationship of rearfoot eversion with tibial internal rotation and hip adduction (peak and range of motion).

FINDINGS

Greater peak rearfoot eversion was associated with greater peak tibial internal rotation in the patellofemoral pain syndrome group (r=0.394, P=0.046). Greater rearfoot eversion range of motion was associated with greater hip adduction range of motion in the patellofemoral pain syndrome (r=0.573, P=0.002) and control (r=0.460, P=0.041) groups; and greater peak hip adduction in the control group (r=0.477, P=0.033).

INTERPRETATION

Associations between greater rearfoot eversion and greater hip adduction indicate that interventions targeted at the foot or hip in individuals with patellofemoral pain syndrome may have similar overall effects on lower limb motion and clinical outcomes. The relationship between rearfoot eversion and tibial internal rotation identified in the patellofemoral pain syndrome group may be related to aetiology. However, additional prospective research is needed to confirm this.

Electromyographic analysis of trunk and hip muscles during resisted lateral band walking

The purpose of this study was to simultaneously quantify bilateral activation/recruitment levels (% maximum voluntary isometric contraction [MVIC]) for trunk and hip musculature on both moving and stance lower limbs during resisted lateral band walking. Differential electromyographic (EMG) activity was recorded in neutral, internal, and external hip rotation in 21 healthy participants. EMG signals were collected with DE-3.1 double-differential surface electrodes at a sampling frequency of 1,000 Hz during three consecutive lateral steps. Gluteus medius average EMG activation was greater (p = 0.001) for the stance limb (52 SD 18% MVIC) than moving limb (35 SD 16% MVIC). Gluteus maximus EMG activation was greater (p = 0.002) for the stance limb (19 SD 13% MVIC) than moving limb (13 SD 9% MVIC). Erector spinae activation was greater (p = 0.007) in hip internal rotation (30 SD 13% MVIC) than neutral rotation (26 SD 10% MVIC) and the moving limb (31 SD 15% MVIC) was greater (p = 0.039) than the stance limb (23 SD 11% MVIC). Gluteus medius and maximus muscle activation were greater on the stance limb than moving limb during resisted lateral band walking. Therefore, clinicians may wish to consider using the involved limb as the stance limb during resisted lateral band walking exercise.

The effect on human balance of standing with toe-extension

Background

Postural balance is vital for safely carrying out many daily activities, such as locomotion. The purpose of this study was to determine how changes in normal standing (NS) and standing with toe-extension (SWT) impact postural control during quiet standing. Furthermore, the research aimed to examine the extent to which the effect of these factors differed between genders.

Methodology/Principal Findings

Thirty healthy young adults (age = 21.2±1.3 y; height = 1.63±0.07 m; mass = 56.0±9.3 kg) with no prior lower limb injuries participated in the study. A postural stability test using the Biodex Balance System was used for both NS and SWT conditions. The three measurements from the BBS were Overall Stability Index (OSI), Medial-Lateral Stability Index (MLSI) and Anterior-Posterior Stability Index (APSI). No significant difference was found between NS and SWT in the OSI, MLSI or APSI (F_{2, 28} = 3.357, p = 0.077). The main difference between the stability index scores was significant (F_{2, 28} = 275.1, p<0.001). The Bonferroni post-hoc test showed significant differences between the OSI and MLSI (p<0.001); the OSI and APSI (p<0.001); and the MLSI and the APSI (p<0.001). Significant differences were found during NS (p<0.001), for the MLSI when compared with the APSI, but this was not found during the SWT condition. Additionally, no gender effects were proven to exist that altered postural sway during quiet standing.

Conclusions/Significance

This study reveals significant interaction between the stability indices measured; OSI, APSI and MLSI in both NS and SWT. Standing with toe extended does not have a significant impact on an individual’s ability to control their balance during normal quiet standing. However, the findings revealed that the sway tendency in the medial-lateral direction might serve as a factor in an individual’s ability to regain balance.

The influence of hip abductor muscle performance on dynamic postural stability in females with patellofemoral pain

Hip abductors play an important role in maintaining trunk and pelvis stability during unipedal tasks. The purpose of the study was to compare postural stability between individuals with patellofemoral pain (PFP) and pain-free controls. A secondary purpose was to evaluate the effect of a hip stabilizing brace on postural stability. Twenty females with PFP (27.3±6.3 years) and 19 controls (26.1±4.5 years) participated. Each subject performed a unipedal step-down balance task with the stance leg on a force platform from which center of pressure (COP) excursion was recorded. Quantitative COP excursion patterns (mean and peak displacements) were used as measures of postural stability. For subjects with PFP, postural stability also was quantified following the application of a hip stabilizing brace. Hip abductor strength was significantly lower in PFP group compared to the control group (1.39±0.4 vs. 1.62±0.26 N/kg-BW, p=0.046). Peak and mean medial-lateral COP displacements during the balance task were greater in the PFP group (39.8±6.7 vs. 24.3±3.8 mm, p<0.001; 24.7±16.3 vs. 13.5±4.4 mm, p=0.005). Application of the hip stabilizing brace reduced the peak and mean COP displacement (39.8±6.7 vs. 24.7±4.7 mm, p<0.001; 24.7±16.3 vs. 16.8±15.1 mm, p=0.02). Our results demonstrate that females with PFP exhibit impaired medial-lateral postural stability when compared to control subjects. Application of a hip stabilizing brace significantly improved stability to a level comparable to the controls.

The effect of pain on hip and knee kinematics during running in females with chronic patellofemoral pain

PURPOSE

Despite the growing recognition of the role of abnormal hip and knee mechanics in patellofemoral pain (PFP), few studies have assessed if or how these mechanics change when the person experiences pain while running. Therefore, the purpose of this study was to determine if the development of pain while running resulted in altered hip and knee kinematics in female runners with PFP as compared to healthy female runners.

METHODS

Thirty female runners (15 PFP, 15 controls) participated in an instrumented gait analysis while running for 30 min at a self-selected pace. Pain and fatigue were recorded every minute while participants ran. Variables of interest included peak hip adduction, hip internal rotation, knee abduction, knee external rotation, pain, and fatigue.

RESULTS

There were significant group by pain interactions for hip adduction (p<0.01) and hip internal rotation (p<0.01). The healthy group, who did not develop pain had significant increases in both motions compared to the PFP group, who did develop pain. There was also a trend toward less knee external rotation in the PFP group in presence of pain (p=0.059). No differences were found for knee abduction (p=0.32). A group main effect was found for hip internal rotation (p=0.008) in which the PFP group had significantly larger values.

CONCLUSION

Runners with PFP did not alter their hip mechanics over the course of the run. This may have resulted in repetitive stress to the same aspect of the patellofemoral joint and contributed to the initial development of pain. However, the PFP group did attempt to make a compensation once in pain by reducing knee external rotation.

Gender differences in trunk, pelvis and lower limb kinematics during a single leg squat

The relationship between trunk and lower limb kinematics in healthy females versus males is unclear since trunk kinematics in the frontal and transverse planes have not been systematically examined with lower limb kinematics. The aim of this study was to investigate the existence of different multi-joints movement strategies between genders during a single leg squat. We expected that compared to males, females would have greater trunk and pelvis displacement due to less trunk control and display hip and knee movement consistent with medial-collapse (i.e. greater hip adduction, hip medial rotation, knee abduction, and knee lateral rotation) on the weight-bearing limb. Nine females and 10 males participated in the study. Kinematic data were collected using an 8-camera, 3D-motion-capture-system. Trunk relative to pelvis, pelvis relative to the laboratory, hip and knee angles in three planes (sagittal, frontal and transverse) were examined at two time events relevant to knee joint mechanics: 45° of knee flexion and peak knee flexion. Females flexed their trunk less than males and rotated their trunk and pelvis toward the weight-bearing limb more than males. Females also displayed greater hip adduction and knee abduction than males. Taken together these results suggest that females and males used different movement strategies during a single leg squat. Females displayed a trunk and pelvic movement pattern that may put them at risk of knee injury and pain.

Changes in muscle activation patterns when running step rate is increased

Running with a step rate 5-10% greater than one's preferred can substantially reduce lower extremity joint moments and powers, and has been suggested as a possible strategy to aid in running injury management. The purpose of this study was to examine how neuromuscular activity changes with an increase in step rate during running. Forty-five injury-free, recreational runners participated in this study. Three-dimensional motion, ground reaction forces, and electromyography (EMG) of 8 muscles (rectus femoris, vastus lateralis, medial gastrocnemius, tibialis anterior, medial and lateral hamstrings, and gluteus medius and maximus) were recorded as each subject ran at their preferred speed for three different step rate conditions: preferred, +5% and +10% of preferred. Outcome measures included mean normalized EMG activity for each muscle at specific periods during the gait cycle. Muscle activities were found to predominantly increase during late swing, with no significant change in activities during the loading response. This increased muscle activity in anticipation of foot-ground contact likely alters the landing posture of the limb and the subsequent negative work performed by the joints during stance phase. Further, the increased activity observed in the gluteus maximus and medius suggests running with a greater step rate may have therapeutic benefits to those with anterior knee pain.

Trunk, pelvis, hip, and knee kinematics, hip strength, and gluteal muscle activation during a single-leg squat in males and females with and without patellofemoral pain syndrome

STUDY DESIGN

Controlled laboratory study using a cross-sectional design.

OBJECTIVES

To determine whether there are any differences between the sexes in trunk, pelvis, hip, and knee kinematics, hip strength, and gluteal muscle activation during the performance of a single-leg squat in individuals with patellofemoral pain syndrome (PFPS) and control participants.

BACKGROUND

Though there is a greater incidence of PFPS in females, PFPS is also quite common in males. Trunk kinematics may affect hip and knee function; however, there is a lack of studies of the influence of the trunk in individuals with PFPS.

METHODS

Eighty subjects were distributed into 4 groups: females with PFPS, female controls, males with PFPS, and male controls. Trunk, pelvis, hip, and knee kinematics and gluteal muscle activation were evaluated during a single-leg squat. Hip abduction and external rotation eccentric strength was measured on an isokinetic dynamometer. Group differences were assessed using a 2-way multivariate analysis of variance (sex by PFPS status).

RESULTS

Compared to controls, subjects with PFPS had greater ipsilateral trunk lean (mean ± SD, 9.3° ± 5.3° versus 6.7° ± 3.0°; P = .012), contralateral pelvic drop (10.3° ± 4.7° versus 7.4° ± 3.8°; P = .003), hip adduction (14.8° ± 7.8° versus 10.8° ± 5.6°; P<.0001), and knee abduction (9.2° ± 5.0° versus 5.8° ± 3.4°; P<.0001) when performing a single-leg squat. Subjects with PFPS also had 18% less hip abduction and 17% less hip external rotation strength. Compared to female controls, females with PFPS had more hip internal rotation (P<.05) and less muscle activation of the gluteus medius (P = .017) during the single-leg squat.

CONCLUSION

Despite many similarities in findings for males and females with PFPS, there may be specific sex differences that warrant consideration in future studies and when clinically evaluating and treating females with PFPS.

Patellofemoral pain: proximal, distal, and local factors, 2nd International Research Retreat

Patellofemoral pain (PFP) is one of the most common lower extremity conditions seen in orthopaedic practice. The mission of the second International Patellofemoral Pain Research Retreat was to bring together scientists and clinicians from around the world who are conducting research aimed at understanding the factors that contribute to the development and, consequently, the treatment of PFP. The format of the 2.5-day retreat included 2 keynote presentations, interspersed with 6 podium and 4 poster sessions. An important element of the retreat was the development of consensus statements that summarized the state of the research in each of the 4 presentation categories. In this supplement, you will find the consensus documents from the meeting, as well as the keynote addresses, schedule, and platform and poster presentation abstracts.

A narrative review of evidence-based recommendations for the physical examination of the lumbar spine, sacroiliac and hip joint complex

Non-specific low back pain is a frequent complaint in primary care, but the differential diagnosis for low back pain can be complex. Despite advances in diagnostic imaging, a specific pathoanatomical source of low back pain can remain elusive in up to 85% of individuals. Best practice guidelines recommend that clinicians conduct a focused physical examination to help to identify patients with non-specific low back pain and an evidence-based course of clinical management. The use of sensitive and specific clinical methods to assess the lumbar spine, sacroiliac and hip joints is critical for effective physical examination. Psychosocial factors also play an important role in the evaluation of individuals with low back pain, but are not included in this narrative review of physical examination methods. Physical examination of the lumbar spine, sacroiliac and hip joints is presented, organized around patient position for efficient and effective clinical assessment.

Knee kinetic pattern during gait and anterior knee pain before and after rehabilitation in patients with patellofemoral pain syndrome

Patellofemoral pain is likely due to compressive force acting on the patella related in turn to knee extension moment. The latter variable was assumed to be (i) reduced during short-distance free walking in case of patellofemoral pain syndrome and (ii) increased after therapeutic pain reduction. Peak knee extension moment at beginning of stance phase was recorded by three-dimensional gait analysis in 22 controls and in 23 patients with patellofemoral pain syndrome before and after rehabilitation of knee extensors and flexors to reduce the pain. Pain would occur mainly in stressful activities such as stair negotiation or squatting and was quantified by the anterior knee pain scale. Peak knee extension moment was significantly reduced in all the patients before treatment (n=23) compared to controls, although no one had pain during free walking. In the 17 patients who experienced significant post-rehabilitation pain reduction in their stressful activities, the peak knee extension moment was significantly reduced before treatment compared to controls and significantly increased after treatment, reaching values similar to control values. The peak knee extension moment during free walking appears to be a good kinetic variable related to a compensatory mechanism limiting or avoiding anterior knee pain and may be of interest in assessing knee dynamics alteration in patients with PFPS.

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.

Effect of functional stabilization training on lower limb biomechanics in women

PURPOSE

This study aimed to verify the effects of functional stabilization training on lower limb kinematics, functional performance, and eccentric hip and knee torques.

METHODS

Twenty-eight women were divided into a training group (TG; n = 14), which carried out the functional stabilization training during 8 wk, and a control group (CG; n = 14), which carried out no physical training. The kinematic assessment of the lower limb was performed during a single-leg squat, and the functional performance was evaluated by way of the single-leg triple hop and the timed 6-m single-leg hop tests. The eccentric hip abductor, adductor, lateral rotator, medial rotator, and the knee flexor and extensor torques were measured using an isokinetic dynamometer.

RESULTS

After 8 wk, the TG significantly reduced the values for knee abduction (from -6.86° to 1.49°), pelvis depression (from -10.21° to -7.86°) and femur adduction (from 7.08° to 5.19°) as well as increasing the excursion of femur lateral rotation (from -0.55° to -3.67°). Similarly, the TG significantly increased the values of single-leg triple hop (from 3.52 to 3.92 m) and significantly decreased the values of timed 6-m single-leg hop tests (from 2.43 to 2.14 s). Finally, the TG significantly increased the eccentric hip abductor (from 1.31 to 1.45 N · m · kg(-1)), hip lateral rotator (from 0.75 to 0.91 N · m · kg(-1)), hip medial rotator (from 1.45 to 1.66 N · m · kg(-1)), knee flexor (from 1.43 to 1.55 N · m · kg(-1)), and knee extensor (from 3.46 to 4.40 N · m · kg(-1)) torques.

CONCLUSIONS

Strengthening of the hip abductor and lateral rotator muscles associated with functional training improves dynamic lower limb alignment and increases the strength and functional performance.

Effects of a lower limb functional exercise programme aimed at minimising knee valgus angle on running kinematics in youth athletes

OBJECTIVES

To investigate the effectiveness of 8-weeks of lower limb functional exercises on frontal plane hip and knee angles during running in youth athletes.

DESIGN

Pre- and post-intervention quantitative experimental.

METHODS

Nineteen athletes (11 male, 8 female, 11.54 ± 1.34 years) from a long-term athletic development programme had 3-dimensional running gait measured pre and post an 8-week exercise intervention. Youth athletes randomised to control (upper limb strengthening exercises) or experimental (lower limb functional exercises aimed at minimising knee valgus angle) interventions completed the exercises during the first 10 min of training, three mornings a week. Pre- and post-parallel groups' analysis provided estimates of intervention effects for control and experimental groups.

RESULTS

Differences in pre- to post-intervention changes in mean frontal plane angles between control and experimental groups were trivial for the left hip (0.1°) and right knee (-0.3°). There was a small beneficial decrease in right hip joint angle (0.4°) but a very large (ES = 0.77, CI 0.1-3.7) detrimental increase in left knee valgus angle (1.9°) between groups.

CONCLUSION

The 8-week lower limb functional exercises had little beneficial effects on lower limb hip and knee mechanics in youth athletes aged 9-14 years.

The effects of quadriceps strengthening on pain, function, and patellofemoral joint contact area in persons with patellofemoral pain

OBJECTIVE

Patellar malalignment is a major cause of patellofemoral pain syndrome (PFPS), but the relationship between clinical symptoms and changes in patellar position and knee muscle strength has not been confirmed. This study examined the effect of weight training on hip and knee muscle strength, patellofemoral joint contact area, and patellar tilt on subjects with and without PFPS, hoping to develop an optimal rehabilitation protocol for subjects with PFPS.

DESIGN

The study uses a prospective independent group comparison. Fifteen subjects with and without PFPS were assessed for knee strength, patellofemoral joint contact area, and patellar tilt angle using magnetic resonance imaging. The subjects with PFPS were also examined and given a numeric pain rating score and a Kujala patellofemoral score. The subjects performed lower-limb weight training 3 times/wk for 8 wks, and the outcomes were assessed both before and after training.

RESULTS

Subjects with PFPS have increased their patellofemoral joint contact area after weight training (P < 0.001). No statistical significant change was found on the patellar tilt angle. The isometric and isokinetic knee strength in subjects with and without PFPS have increased after weight training (P value increased from 0.007 to 0.05). Both numeric pain rating and Kujala patellofemoral score in the PFPS group improved after training (P < 0.001).

CONCLUSIONS

Weight-training exercise increased knee muscle strength and the patellofemoral joint contact area, which could reduce mechanical stress in the joint, improving pain and function in subjects with PFPS.

Suggestions from the field for return-to-sport rehabilitation following anterior cruciate ligament reconstruction: alpine skiing

Alpine skiing is a high-risk sport for injuries to the anterior cruciate ligament (ACL). While descending a hill, a skier must resist large centrifugal forces at a high velocity, while the knees are positioned in postures that place the ACL at risk of injury. Skiers who undergo ACL reconstructive surgery are prone to a high rate of reinjury to the same knee and even ACL injury in the uninjured knee. A rehabilitation program that integrates the best current evidence of ACL rehabilitation and the science of skiing is essential to a successful return to alpine skiing. Unlike rehabilitation programs developed for court or field athletes, a skiing program must place a large emphasis on slow eccentric-loading and weight-bearing (closed-chain) power and endurance. The purpose of this clinical commentary is to provide the rehabilitation specialist such a program directed toward safely returning the athlete to alpine skiing.

Suggestions from the field for return to sports participation following anterior cruciate ligament reconstruction: American football

Returning an American football player to sport after an anterior cruciate ligament reconstruction is challenging on several fronts. First, there are approximately 15 different positions a football player could play, depending on how specifically you define the positions on the field. Each of these positions has specific demands for optimal size, strength, power, body composition, cardiovascular fitness, and movement. Understanding all of these factors is paramount to returning a football player not only to his sport but also to his specific position. Second, the chaotic, contact-rich nature of the sport requires that heavy demands be placed on the lower extremities to attenuate external contact forces from other players and from ground reaction forces associated with accelerating, decelerating, quick stops and starts, and changing direction. Finally, return to a competitive level of performance is further influenced by playing surface, shoe selection, the equipment the player wears, and various potential psychosocial factors. It is the responsibility of the clinician to provide a progressive and systematic rehabilitation program by first introducing preprogrammed movements that, once mastered, are progressed with elements of more reactive and random movement patterns. The precise nature of this systematic progression of advanced rehabilitation is key in developing return-to-play criteria and, ultimately, in readying an American football player for eventual return to sport and a particular position.

Suggestions from the field for return to sports participation following anterior cruciate ligament reconstruction: soccer

Successful return to play remains a challenge for a soccer player after anterior cruciate ligament reconstruction. In addition to a successful surgical intervention, a soccer-specific functional rehabilitation program is essential to achieve this goal. Soccer-like elements should be incorporated in the early stages of rehabilitation to provide neuromuscular training specific to the needs of the player. Gym-based and, later, field-based drills are gradually intensified and progressed until the player demonstrates the ability to return to team practice. In addition to the recovery of basic attributes such as mobility, flexibility, strength, and agility, the surgically repaired knee must also regain soccer-specific neuromuscular control and conditioning for an effective return to sports. The individual coaching of the player by the sports physiotherapist and compliance with the training program by the player are key factors in the rehabilitation process. To minimize reinjury risk and to maximize the player's career, concepts of soccer-specific injury prevention programs should be incorporated into the training routine during and after the rehabilitation of players post-ACL reconstruction.

Suggestions from the field for return to sports participation following anterior cruciate ligament reconstruction: basketball

The purpose of this paper is to outline the final, functional phases of rehabilitation that address exercises, drills, and return-to-play criteria for the sport of basketball, following anterior cruciate ligament (ACL) reconstruction. ACL injuries can be debilitating and affect the quality of life for recreational and elite athletes alike. Tears of the ACL are common in both male and female basketball players, with a higher incidence rate in females. Incidence of a retear to the existing graft or contralateral knee within 5 years of ACL reconstruction with patellar tendon autograft in young (less than 18 to 25 years of age), active basketball players can be as high as 52%. Reducing the number of ACL injuries or reinjury, of which there are an estimated 80 000 per year at an associated cost of over a billion dollars, can have significant potential long-term fiscal and health benefits. Following surgical reconstruction of the ACL, implementing a tailored rehabilitation protocol can ensure a successful return to sport. When searching the literature for such protocols, clinicians may struggle to find specific exercises, drills, and return-to-play criteria for particular sports. The intent of this manuscript is to present such a rehabilitation protocol for basketball.

Anatomic anterior cruciate ligament reconstruction utilizing the double-bundle technique

The goal of every orthopaedic surgeon should be to restore anatomy as close as possible to normal. Intense research on reconstruction of the anterior cruciate ligament (ACL) and an advancing knowledge of the anatomy and function of the 2 primary bundles of the ACL have led to techniques of ACL reconstruction that more closely restore normal anatomy. Restoring the ACL footprint is one of the most important goals of the surgery, and the choice between anatomic single-bundle and double-bundle ACL reconstruction is determined by the anatomical features of each patient. After reconstruction, the graft undergoes a complex, lengthy process of remodeling; therefore, inappropriate (early), aggressive rehabilitation can lead to graft failure and compromise the patient's outcome. The purpose of this article is to provide an overview of the anatomy and function of the ACL, the methods for anatomic single-bundle and double-bundle ACL reconstruction, and our recommendations for postoperative rehabilitation.

Anterior cruciate ligament strain and tensile forces for weight-bearing and non-weight-bearing exercises: a guide to exercise selection

There is a growing body of evidence documenting loads applied to the anterior cruciate ligament (ACL) for weight-bearing and non-weight-bearing exercises. ACL loading has been quantified by inverse dynamics techniques that measure anterior shear force at the tibiofemoral joint (net force primarily restrained by the ACL), ACL strain (defined as change in ACL length with respect to original length and expressed as a percentage) measured directly in vivo, and ACL tensile force estimated through mathematical modeling and computer optimization techniques. A review of the biomechanical literature indicates the following: ACL loading is generally greater with non-weight-bearing compared to weight-bearing exercises; with both types of exercises, the ACL is loaded to a greater extent between 10° to 50° of knee flexion (generally peaking between 10° and 30°) compared to 50° to 100° of knee flexion; and loads on the ACL change according to exercise technique (such as trunk position). Squatting with excessive forward movement of the knees beyond the toes and with the heels off the ground tends to increase ACL loading. Squatting and lunging with a forward trunk tilt tend to decrease ACL loading, likely due to increased hamstrings activity. During seated knee extension, ACL force decreases when the resistance pad is positioned more proximal on the anterior aspect of the lower leg, away from the ankle. The evidence reviewed as part of this manuscript provides objective data by which to rank exercises based on loading applied to the ACL. The biggest challenge in exercise selection post-ACL reconstruction is the limited knowledge of the optimal amount of stress that should be applied to the ACL graft as it goes through its initial incorporation and eventual maturation process. Clinicians may utilize this review as a guide to exercise selection and rehabilitation progression for patients post-ACL reconstruction.

Recent advances in the rehabilitation of anterior cruciate ligament injuries

Rehabilitation following anterior cruciate ligament surgery continues to change, with the current emphasis being on immediate weight bearing and range of motion, and progressive muscular strengthening, proprioception, dynamic stability, and neuromuscular control drills. The rehabilitation program should be based on scientific and clinical research and focus on specific drills and exercises designed to return the patient to the desired functional goals. The goal is to return the patient's knee to homeostasis and the patient to his or her sport or activity as safely as possible. Unique rehabilitation techniques and special considerations for the female athlete will also be discussed. The purpose of this article is to provide the reader with a thorough scientific basis for anterior cruciate ligament rehabilitation based on graft selection, patient population, and concomitant injuries.

Current concepts for rehabilitation and return to sport after knee articular cartilage repair in the athlete

Articular cartilage injury is observed with increasing frequency in both elite and amateur athletes and results from the significant acute and chronic joint stress associated with impact sports. Left untreated, articular cartilage defects can lead to chronic joint degeneration and athletic and functional disability. Treatment of articular cartilage defects in the athletic population presents a therapeutic challenge due to the high mechanical demands of athletic activity. Several articular cartilage repair techniques have been shown to successfully restore articular cartilage surfaces and allow athletes to return to high-impact sports. Postoperative rehabilitation is a critical component of the treatment process for athletic articular cartilage injury and should take into consideration the biology of the cartilage repair technique, cartilage defect characteristics, and each athlete's sport-specific demands to optimize functional outcome. Systematic, stepwise rehabilitation with criteria-based progression is recommended for an individualized rehabilitation of each athlete not only to achieve initial return to sport at the preinjury level but also to continue sports participation and reduce risk for reinjury or joint degeneration under the high mechanical demands of athletic activity.

Risk factors for patellofemoral pain syndrome: a systematic review

STUDY DESIGN

Systematic review.

OBJECTIVES

To systematically outline the risk factors for patellofemoral pain syndrome (PFPS).

BACKGROUND

PFPS is the most commonly diagnosed condition in young individuals with knee complaints. High incidence among athletes suggests a possibility of prevention. The first step toward prevention is identification of possible risk factors.

METHODS

Prospective studies that included 20 or more patients with PFPS and examined at least 1 possible risk factor for PFPS were included. An assessment list was applied to evaluate the quality of the studies. A meta-analysis was conducted using a random-effects model. Significant differences were based on calculated mean differences, with matching 95% confidence intervals (CIs). For dichotomous data, odds ratios or relative risks were calculated.

RESULTS

Of the 3845 potentially relevant articles, 7 were included in this review. These studies examined a total of 135 variables, and pooling was possible for 13 potential risk factors. The pooled data showed that knee extension peak torques were significantly lower in the PFPS group than in controls. Mean differences in torque, with negative differences reflecting lower means in the PFPS group, were as follows: (a) standardized relative to body weight at 60°/s, -0.24 Nm (95% CI: -0.39, -0.09); (b) standardized relative to body weight at 240°/s, -0.11 Nm (95% CI: -0.17, -0.05); (c) standardized relative to body mass index at 60°/s, -0.84 Nm (95% CI: -1.23, -0.44); (d) standardized relative to body mass index at 240°/s, -0.32 Nm (95% CI: -0.52, -0.12); (e) nonstandardized in a concentric mode at 60°/s, -17.54 Nm (95% CI: -25.53, -9.54); (f) nonstandardized in a concentric mode at 240°/s, -7.72 Nm (95% CI: -12.67, -2.77).

CONCLUSION

Weaker knee extension strength, expressed by peak torque, appears to be a risk factor for PFPS, based on meta-analyses of pooled results from multiple studies. Because several other risk factors for PFPS were described only in single studies, these additional risk factors, as well as those with conflicting evidence, need to be confirmed in future studies.

LEVEL OF EVIDENCE

Prognosis, level 1a-.

The effects of isolated hip abductor and external rotator muscle strengthening on pain, health status, and hip strength in females with patellofemoral pain: a randomized controlled trial

STUDY DESIGN

Randomized controlled trial.

OBJECTIVES

To examine the effectiveness of isolated hip abductor and external rotator strengthening on pain, health status, and hip strength in females with patellofemoral pain (PFP).

BACKGROUND

Altered hip kinematics resulting from hip muscle weakness has been proposed as a contributing factor in the development of PFP. To date, no study has examined clinical outcomes associated with isolated hip muscle strengthening in those with PFP.

METHODS

Twenty-eight females with PFP were sequentially assigned to an exercise (n = 14) or a no-exercise control group (n = 14). The exercise group completed bilateral hip abductor and external rotator strengthening 3 times per week for 8 weeks. Pain (visual analog scale), health status (WOMAC), and hip strength (handheld dynamometer) were assessed at baseline and postintervention. Pain and health status were also evaluated at 6 months postintervention in the exercise group. Two-factor mixed-model analyses of variance were used to determine the effects of the intervention on each outcome variable.

RESULTS

Significant group-by-time interactions were observed for each variable of interest. Post hoc testing revealed that pain, health status, and bilateral hip strength improved in the exercise group following the 8-week intervention but did not change in the control group. Improvements in pain and health status were sustained at 6-month follow-up in the exercise group.

CONCLUSION

A program of isolated hip abductor and external rotator strengthening was effective in improving pain and health status in females with PFP compared to a no-exercise control group. The incorporation of hip-strengthening exercises should be considered when designing a rehabilitation program for females with PFP.

LEVEL OF EVIDENCE

Therapy, level 2b.

Musculoskeletal myths

This paper discusses a number of common myths in the musculoskeletal pain management and rehabilitation/athletic development fields. The origins or rationale for these beliefs are reviewed. New scientific evidence disputing or refuting the myth is then presented followed by and explanation and evidence for an updated perspective.

Landing pattern modification to improve patellofemoral pain in runners: a case series

STUDY DESIGN

Case series.

BACKGROUND

Patellofemoral pain is a common overuse injury in runners. Recent findings suggest that patellofemoral pain is related to high-impact loading associated with a rearfoot strike pattern. This case series describes the potential training effects of a landing pattern modification program to manage patellofemoral pain in runners.

CASE DESCRIPTION

Three female runners with unilateral patellofemoral pain who initially presented with a rearfoot strike pattern underwent 8 sessions of landing pattern modification program using real-time audio feedback from a force sensor placed within the shoe. Ground reaction forces during running were assessed with an instrumented treadmill. Patellofemoral pain symptoms were assessed using 2 validated questionnaires. Finally, running performance was measured by self-reported best time to complete a 10-km run in the previous month. The runners were assessed before, immediately after, and 3 months following training.

OUTCOMES

The landing pattern of runners was successfully changed from a rearfoot to a nonrearfoot strike pattern after training. This new pattern was maintained 3 months after the program. The vertical impact peak and rates of loading were shown to be reduced. Likewise, the symptoms related to patellofemoral pain and associated functional limitations were improved. However, only 1 of the participants reported improved running performance after the training.

DISCUSSION

This case series provided preliminary data to support further investigation of interventions leading to landing pattern modification in runners with patellofemoral pain.

LEVEL OF EVIDENCE

Therapy, level 4.

Iliotibial band syndrome: soft tissue and biomechanical factors in evaluation and treatment

Muscle performance factors and altered loading mechanics have been linked to a variety of lower extremity musculoskeletal disorders. In this article, biomechanical risk factors associated with iliotibial band syndrome (ITBS) are described, and a strategy for incorporating these factors into the clinical evaluation of and treatment for that disorder is presented. Abnormal movement patterns in runners and cyclists with ITBS are discussed, and the pathophysiological characteristics of this syndrome are considered in light of prior and current studies in anatomy. Differential diagnoses and the use of imaging, medications, and injections in the treatment of ITBS are reviewed. The roles of hip muscle strength, kinematics, and kinetics are detailed, and the assessment and treatment of muscle performance factors are discussed, with emphasis on identifying and treating movement dysfunction. Various stages of rehabilitation, including strengthening progressions to reduce soft-tissue injury, are described in detail. ITBS is an extremely common orthopedic condition that presents with consistent dysfunctional patterns in muscle performance and movement deviation. Through careful assessment of lower quarter function, the clinician can properly identify individuals and initiate treatment.

Relationship between eccentric hip torque and lower-limb kinematics: gender differences

The purposes of this study were to compare lower-limb kinematics between genders, and determine the relationships among eccentric hip abductor and lateral rotator torques and lower-limb kinematics. The movements of the pelvis, femur, and knee were calculated for 16 women and 16 men during the single-leg squat. Eccentric hip abductor and lateral rotator torques were measured using an isokinetic dynamometer. The results showed that women had greater contralateral pelvic depression, femur adduction, and knee abduction than men. The eccentric hip abductor and lateral rotator torques were correlated with coronal plane femur and knee movements in the overall sample. When the genders were analyzed separately, it was observed that women with greater eccentric hip abductor torque exhibited less femur adduction and femur medial rotation, and greater knee adduction excursion. No significant relationship was observed between the isokinetic and kinematic variables in the male group. The differences between the genders help to explain the greater rate of knee disorders observed in women. Moreover, the eccentric hip abduction action seemed to be more important in women to control the lower-limb movements.

The effect of a hip-strengthening program on mechanics during running and during a single-leg squat

STUDY DESIGN

Block randomized controlled trial.

OBJECTIVES

To investigate whether a strengthening and movement education program, targeting the hip abductors and hip external rotators, alters hip mechanics during running and during a single-leg squat.

BACKGROUND

Abnormal movement patterns during running and single-leg squatting have been associated with a number of running-related injuries in females. Therapeutic interventions for these aberrant movement patterns typically include hip strengthening. While these strengthening programs have been shown to improve symptoms, it is unknown if the underlying mechanics during functional movements is altered.

METHODS

Twenty healthy females with excessive hip adduction during running, as determined by instrumented gait analysis, were recruited. The runners were matched by age and running distance, and randomized to either a training group or a control group. The training group completed a hip strengthening and movement education program 3 times per week for 6 weeks in addition to single-leg squat training with neuromuscular reeducation consisting of mirror and verbal feedback on proper mechanics. The control group did not receive an intervention but maintained the current running distance. Using a handheld dynamometer and standard motion capture procedures, hip strength and running and single-leg squat mechanics were compared before and after the strengthening and movement education program.

RESULTS

While hip abductor and external rotation strength increased significantly (P<.005) in the training group, there were no significant changes in hip or knee mechanics during running. However, during the single-leg squat, hip adduction, hip internal rotation, and contralateral pelvic drop all decreased significantly (P = .006, P = .006, and P = .02, respectively). The control group exhibited no changes in hip strength, nor in the single-leg squat or running mechanics at the conclusion of the 6-week study.

CONCLUSION

A training program that included hip strengthening and movement training specific to single-leg squatting did not alter running mechanics but did improve single-leg squat mechanics. These results suggest that hip strengthening and movement training, when not specific to running, do not alter abnormal running mechanics.

LEVEL OF EVIDENCE

Therapy, level 2b.

Physiotherapist agreement when visually rating movement quality during lower extremity functional screening tests

OBJECTIVES

To investigate physiotherapist agreement in rating movement quality during lower extremity functional tests using two visual rating methods and physiotherapists with differing clinical experience.

DESIGN

Clinical measurement.

PARTICIPANTS

Six healthy individuals were rated by 44 physiotherapists. These raters were in three groups (inexperienced, novice, experienced).

MAIN MEASURES

Video recordings of all six individuals performing four lower extremity functional tests were visually rated (dichotomous or ordinal scale) using two rating methods (overall or segment) on two occasions separated by 3-4 weeks. Intra and inter-rater agreement for physiotherapists was determined using overall percentage agreement (OPA) and the first order agreement coefficient (AC1).

RESULTS

Intra-rater agreement for overall and segment methods ranged from slight to almost perfect (OPA: 29-96%, AC1: 0.01 to 0.96). AC1 agreement was better in the experienced group (84-99% likelihood) and for dichotomous rating (97-100% likelihood). Inter-rater agreement ranged from fair to good (OPA: 45-79%; AC1: 0.22-0.71). AC1 agreement was not influenced by clinical experience but was again better using dichotomous rating.

CONCLUSIONS

Physiotherapists' visual rating of movement quality during lower extremity functional tests resulted in slight to almost perfect intra-rater agreement and fair to good inter-rater agreement. Agreement improved with increased level of clinical experience and use of dichotomous rating.

Hip muscle weakness in patients with symptomatic femoroacetabular impingement

OBJECTIVE

Femoroacetabular impingement (FAI) is a pathomechanical process, which may cause hip pain, disability and early development of hip osteoarthritis (OA) in young and active adults. Patients with FAI experience functional disability during dynamic weight-bearing activities, which could originate from weakness of the hip muscles. The objective of this study was to compare hip muscle strength between patients with symptomatic FAI and healthy controls. It was hypothesized that patients would present overall hip muscle weakness compared to controls.

METHODS

A total of 22 FAI patients and 22 controls matched for gender, age, and body mass participated in the study. We evaluated isometric maximal voluntary contraction (MVC) strength of all hip muscle groups using hand-held and isokinetic dynamometry, and electromyographic (EMG) activity of the rectus femoris (RF) and tensor fasciae latae (TFL) muscles during active flexion of the hip.

RESULTS

FAI patients had significantly lower MVC strength than controls for hip adduction (28%), flexion (26%), external rotation (18%) and abduction (11%). TFL EMG activity was significantly lower in FAI patients compared with controls (P=0.048), while RF EMG activity did not differ significantly between the two groups (P=0.056).

CONCLUSIONS

Patients with symptomatic FAI presented muscle weakness for all hip muscle groups, except for internal rotators and extensors. Based on EMG recordings, it was demonstrated that patients with symptomatic FAI have a reduced ability to activate TFL muscle during hip flexion. These findings provide orthopedic surgeons with objective information about the amount and specificity of hip muscle weakness in patients with FAI. Future research should investigate the relationship between hip muscle weakness, functional disability and overuse injury risks, as well as the effects of hip muscle strengthening on clinical outcomes in individuals with symptomatic FAI.

Successful rehabilitation of a recreational endurance runner: initial validation for the Bunkie test

This case report details the musculoskeletal evaluation and the successful rehabilitation of a 24-year-old female recreational distance runner who self-referred to physical therapy with an acute bout of low back pain (LBP). Her LBP was provoked during each distance run. The patient's musculoskeletal evaluation revealed core weakness, especially on the left. A recently reported functional test, the Bunkie test, was administered as part of the physical evaluation. The scores from the Bunkie test correlated with other quantitative and qualitative findings. A therapeutic exercise program emphasizing core stabilization was prescribed. The patient was able to shortly return to running pain-free.

Relationship among eccentric hip and knee torques, symptom severity and functional capacity in females with patellofemoral pain syndrome

OBJECTIVE

To determine the relationships between eccentric hip and knee torques, symptom severity and functional capacity in females with patellofemoral pain syndrome (PFPS).

DESIGN

Within-subject correlational study.

SETTING

University biomechanics laboratory.

PARTICIPANTS

10 females diagnosed with PFPS.

MAIN OUTCOME MEASURES

Eccentric strength of the hip abductors and lateral rotators, and knee extensors were assessed using an isokinetic dynamometer. A 10-cm visual analog scale was used to determine usual knee pain in the last week. The Anterior Knee Pain Scale (AKPS) was used to determine the functional capacity of the patients.

RESULTS

The study found that the greater the eccentric knee extensor and hip lateral rotator torques, the higher the functional capacity of the patients (p = 0.02, r = 0.72; p = 0.02, r = 0.72). It was also shown that the greater hip lateral rotator torque, the less the usual pain reported in the last week (p = 0.004, r = -0.84). Despite the lack of statistical significance (p = 0.11), it was also found a modest negative relationship between the eccentric knee extensor torque and the usual pain reported in the last week (r = -0.56) that was considered clinically meaningful (d = 1.4).

CONCLUSIONS

This study showed that eccentric knee extensor and hip lateral rotator torques were associated with functional capacity and pain level in females with PFPS. Further investigations should be carried out to verify the effects of an intervention program focused on the eccentric action of these muscles with respect to the symptoms in patients with PFPS.

Utilization of modified NFL combine testing to identify functional deficits in athletes following ACL reconstruction

STUDY DESIGN

Case control.

OBJECTIVES

To use modified NFL Combine testing methodology to test for functional deficits in athletes following anterior cruciate ligament (ACL) reconstruction following return to sport.

BACKGROUND

There is a need to develop objective, performance-based, on-field assessment methods designed to identify potential lower extremity performance deficits and related impairments in this population.

METHODS

Eighteen patients (mean ± SD age, 16.9 ± 2.1 years; height, 170.0 ± 8.7 cm; body mass, 71.9 ± 21.8 kg) who returned to their sport within a year following ACL reconstruction (95% CI: 7.8 to 11.9 months from surgery) participated (ACLR group). These individuals were asked to bring 1 or 2 teammates to serve as control participants, who were matched for sex, sport, and age (n = 20; mean ± SD age, 16.9 ± 1.1 years; height, 169.7 ± 8.4 cm; body mass, 70.1 ± 20.7 kg). Functional performance was tested using the broad jump, vertical jump, modified long shuttle, modified pro shuttle, modified agility T-test, timed hop, triple hop, single hop, and crossover hop tests. A 1-way multivariate analysis of variance (MANOVA) was used to evaluate group differences for dependent performance variables.

RESULTS

The functional performance measurements of skills requiring bilateral involvement of both lower extremities showed no group differences between the ACLR and control groups (P>.05). An overall group difference (P = .006) was observed for the combined limb symmetry index (LSI) measures. However, the modified double-limb performance tasks (long shuttle, modified agility T-test, and pro shuttle) were not, independently, sufficiently sensitive to detect limb deficits in individuals with ACL reconstruction. Conversely, the LSI on the distance measures of the single-limb performance tasks all provided moderate to large effect sizes to differentiate between the ACLR and control groups, as the individuals who had ACL reconstruction demonstrated involved limb deficits on all measures (P<.05). Finally, the LSI for the timed hop test was not different between groups (P>.05).

CONCLUSIONS

These findings indicate that, while unilateral deficits are present in individuals following ACL reconstruction, they may not be evident during bipedal performance or during modified versions of double-limb performance activities. Isolation of the involved limb with unilateral hopping tasks should be used to identify deficits in performance.

Nonsurgical treatment of acetabular labrum tears: a case series

STUDY DESIGN

Case series.

BACKGROUND

While the literature has emphasized surgical treatment of acetabular labrum tears, there is a lack of information regarding conservative treatment. The purpose of this case series was to describe a nonsurgical program for those with clinical evidence of an acetabular labrum tear, that emphasized hip and lumbopelvic stabilization, correction of hip muscle imbalance, biomechanical control, and sport-specific functional progression.

CASE DESCRIPTION

The 4 patients in this series had clinical evidence and magnetic resonance imaging confirmation of an acetabular labrum tear and underwent a similar treatment protocol consisting of 3 phases. Phase 1 emphasized pain control, education in trunk stabilization, and correction of abnormal joint movement. Phase 2 focused on muscular strengthening, recovery of normal range of motion (ROM), and initiation of sensory motor training. And phase 3 emphasized advanced sensory motor training, with sport-specific functional progression. ROM, flexibility, pain, special tests, and level of function were assessed, and strength was measured with handheld dynamometry.

OUTCOMES

All patients demonstrated decreased pain, functional improvement, and correction of muscular imbalance. Increased muscle strength, primarily for the hip flexors (1%-39%), abductors (18%-56%), and extensors (68%-139%) was also noted.

DISCUSSION

All patients responded well to our program. This case series suggests that patients with clinical evidence of an acetabular labral tear confirmed with MRI can show meaningful improvement with nonsurgical intervention.

LEVEL OF EVIDENCE

Therapy, level 4.

Longitudinal gait and strength changes prior to and following an anterior cruciate ligament rupture and surgical reconstruction: a case report

STUDY DESIGN

Case report.

BACKGROUND

Cross-sectional studies have examined deficits following anterior cruciate ligament (ACL) rupture and subsequent reconstructive surgery. Few studies present preinjury data that may assist in identifying risk factors for ACL rupture. This case report compares gait and strength measures obtained prior to ACL rupture, with follow-up assessments of these measures after rupture and reconstructive surgery.

CASE DESCRIPTION

A 23-year-old woman sustained a noncontact rupture of her right ACL. Kinematic and kinetic gait data were collected using 3-dimensional motion analysis and a synchronized force plate. Knee strength was measured using an isokinetic dynamometer. Data for knee active range of motion (AROM) and the Lower Extremity Functional Scale (LEFS) were also collected. The analyses were descriptive and interpreted based on previously published minimal detectable change and minimal clinically important difference values.

OUTCOMES

Before her injury, the patient demonstrated a low external knee flexion moment during gait. Kinematic and kinetic gait abnormalities were present following rupture and persisted at 13 months postsurgery. The patient demonstrated knee strength deficits following ACL rupture and surgery. Steady gains in LEFS and knee AROM occurred following rupture and surgery.

DISCUSSION

Preinjury data may identify risk factors for ACL rupture. Future studies should examine whether a low external knee flexion moment during gait or sport-related activity is a risk factor for ACL rupture. The patient demonstrated deficits in gait and strength that persisted at 13 months postsurgery.

LEVEL OF EVIDENCE

Therapy, level 4.

A national survey of the physiotherapy management of patients following first-time patellar dislocation

OBJECTIVES

The purpose of this study was to determine how musculoskeletal physiotherapists in acute National Health Service (NHS) hospitals manage patients following a first time patellar dislocation.

DESIGN

National survey study.

SETTING

All NHS acute hospitals with an accident and emergency and/or an orthopaedic department were surveyed.

PARTICIPANTS

306 institutions were surveyed.

INTERVENTIONS

Each institution was sent a 14 question self-administered questionnaire pertaining to the assessment, treatment, evaluation and outcome of patients following a first time patellar dislocation. After 3 weeks, all non-respondents were sent a reminder letter. After a further 3 weeks, those who had not responded by this time were sent a final reminder and copy of the questionnaire.

RESULTS

The survey response rate was 59%. The respondents indicated that first-time patellar dislocation was not a common musculoskeletal disorder managed by NHS physiotherapists, constituting an average of 2% of caseloads. The results suggested that physiotherapists most commonly assess for reduced quadriceps or VMO capacity, gait, patellar tracking and glide, and knee effusion when examining patients following a first-time patellar dislocation. The most common treatments adopted are reassurance, behaviour modification followed by proprioceptive, knee mobility, quadriceps and specific VMO exercises.

CONCLUSIONS

Generic lower limb assessment and treatment strategies are widely used to manage this patient group. Given the previous paucity in this literature, further study is now recommended to assess the efficacy of these interventions to provide UK physiotherapists with an evidence-base to justify their management strategies.

Walking kinematics in individuals with patellofemoral pain syndrome: a case-control study

Patellofemoral pain syndrome (PFPS) development is considered to be multifactorial with various knee, hip and foot/ankle kinematic factors thought to be involved. A paucity of research evaluating kinematic factors throughout the lower limb kinematic chain simultaneously in individuals with PFPS was identified in a recent systematic review. The objective of this study was to compare kinematics at the knee, hip and foot/ankle in a group of individuals with PFPS to a group of asymptomatic controls. Twenty-six individuals with PFPS and 20 controls aged between 18 and 35 were recruited. Between-group comparisons were made for magnitude and timing of peak angles, and range of motion at the forefoot (dorsiflexion, abduction and supination), rearfoot (dorsiflexion, internal rotation and eversion), knee (flexion, abduction and internal rotation) and hip (adduction and internal rotation) during walking. The PFPS group demonstrated less peak hip internal rotation (7.0° versus 11.8°, p=0.024, p=0.024), earlier peak rearfoot eversion relative to the laboratory (30.4% versus 35.3% of the gait cycle, p=0.010) and tibia (32.7% versus 36.5% of the gait cycle, p=0.030), and greater rearfoot dorsiflexion range of motion relative to the laboratory (72.3° versus 68.2°, p=0.007). Additionally, a trend toward reduced gait velocity (p=0.070) was found in the PFPS group. Reduced peak hip internal rotation and gait velocity in individuals with PFPS may indicate compensation to reduce PFJ load during walking. However, earlier peak rearfoot eversion may be a factor related to the pathomechanical development of the condition.