Effects of ankle joint effusion on lower leg function

Magnetic resonance imaging of ankle disorders in adult Nigerians in Lagos

Objectives:

The aim of this study was to establish the frequency, distribution, and spectrum of abnormalities on ankle magnetic resonance imaging (MRI) in adult Nigerians.

Materials and Methods:

A retrospective analysis of ankle MRI of 50 adult patients was conducted at a single health facility. All adult Nigerians with complete clinical data, MRI images, and radiologists’ reports were included. The clinical history and ankle MRI findings were recorded and analysed. The threshold for statistical significance was established at P≤0.05.

Results:

There were 50 subjects comprising 27 males (54%) and 23 females (46%) aged 25–66 years (mean age = 42.84 ± 9.63 years). The right ankle was evaluated in 27 subjects (54%), while the left ankle was studied in 23 (46%). There was a history of trauma in 40 subjects (80%; 27 right ankles and 13 left ankles). Ankle joint effusion was the most common abnormality—seen in 50% of all subjects and in 62.5% of those with antecedent trauma. Achilles tendinosis and Kager (pre-Achilles) fat pad oedema (8–12%), deltoid ligament tear (8%), and medial malleolar fracture (4%) were the other frequently detected pathologies. The other pathologies detected were posterior tibial tendinosis (2%), plantar fasciopathy (2%), and talar contusion (2%). Joint effusion was significantly more prevalent in post-traumatic ankles than in the non-traumatic ankles and in the right ankles than the left ankles. There was no significant difference in the frequency of ankle abnormalities between the male and female subjects and between subjects younger than and older than the mean age.

Conclusion:

Joint effusion, deltoid ligament tear, and Achilles tendinopathy were the prevalent derangements in evaluated ankle joints. Trauma was the main indication for ankle MRI in this study.

Effects of proprioceptive training on ankle muscle strength in fencers: A clinical trial

BACKGROUND

Fencing is a combat sport, which depends of lower limbs muscular strength and neuromuscular function. Because of that, approximately half of all injuries occur in lower limbs, especially in ankle. Thus, the objective of this study was to verify the influence of a twelve-week proprioceptive training program on ankle muscular strength and muscular balance in fencers.

METHODS

The study was a clinical trial, with 19 fencing athletes from 14 to 35-year-old. The main outcome was ankle invertors, evertors, plantiflexors and dorsiflexors muscular strength and ankle muscle balance. The study was performed in six stages: familiarization of muscular strength test in isokinetic dynamometer; pre-intervention; intervention; post-intervention; three- and six-months follow-up. At pre-intervention stage, the muscular strength was evaluated. At intervention stage, the athletes performed 12-week proprioceptive training program, three times a week. At post-intervention, three- and the six-months follow-ups, same pre-intervention test was performed.

RESULTS

The proprioceptive training improved front leg ankle dorsiflexor strength at three- and six-months follow-ups compared to pre-intervention. Furthermore, training increased the front leg dorsiflexors/plantiflexors conventional ratio at three- and six-months follow-ups compared to pre-intervention; and evertors/invertors conventional ratio at three-months follow-up compared to pre-intervention; and evertors/invertors functional ratio at post-intervention and three- and six-months follow-ups compared to pre-intervention.

CONCLUSIONS

The improvement and/or maintenance of ankle muscle strength occurred in intervention group seems to be due to stimulus provided by proprioceptive training, with ankle dorsiflexors being the most stimulated group.

Rehabilitation of the Dancer

Rehabilitation of dance injury should be a team-based approach lead by a medical practitioner with experience in both musculoskeletal medicine and dance specific demands. The rehabilitation protocol begins with a dance specific initial assessment, followed by injury management, progression of the rehabilitation program including dance specific movement, advancing to full independence.

Best Evidence Rehabilitation for Chronic Pain Part 5: Osteoarthritis

Osteoarthritis (OA) is a leading cause of chronic pain and disability in older adults, which most commonly affects the joints of the knee, hip, and hand. To date, there are no established disease modifying interventions that can halt or reverse OA progression. Therefore, treatment is focused on alleviating pain and maintaining or improving physical and psychological function. Rehabilitation is widely recommended as first-line treatment for OA as, in many cases, it is safer and more effective than the best-established pharmacological interventions. In this article, we describe the presentation of OA pain and give an overview of its peripheral and central mechanisms. We then provide a state-of-the-art review of rehabilitation for OA pain—including self-management programs, exercise, weight loss, cognitive behavioral therapy, adjunct therapies, and the use of aids and devices. Next, we explore several promising directions for clinical practice, including novel education strategies to target unhelpful illness and treatment beliefs, methods to enhance the efficacy of exercise interventions, and innovative, brain-directed treatments. Finally, we discuss potential future research in areas, such as treatment adherence and personalized rehabilitation for OA pain.

The Reliability of Neurological Measurement in the Vastus Medialis: Implications for Research and Practice

The integrity of the corticomotor pathway is paramount in the optimal functioning of skeletal muscle. However, variability of neurophysiological assessment via peripheral nerve and transcranial magnetic stimulation can render interpretation difficult. Seldom evidence exists regarding the reliability of such measurements in the leg extensors, which have important locomotive and functional roles. This study aimed to assess the test-retest reliability of peripheral, corticospinal and intracortical responses in the vastus medialis. Transcranial magnetic and direct current electrical nerve stimulation were delivered to sixteen healthy young adults (8M and 8F) on two separate occasions. The Hoffmann reflex, maximal compound wave, motor evoked potential, corticospinal silent period, intracortical facilitation, and short-interval intracortical inhibition were recorded from the vastus medialis at rest, and during controlled submaximal voluntary contraction. Relative reliability was quantified using intra-class correlation coefficient (ICC2,1). Absolute reliability was quantified using standard error of measurement (SEm) and minimal detectable change (MDC). Corticospinal silent period, corticospinal silent period/motor evoked potential ratio, active motor evoked potential, maximal Hoffman reflex, and passive short-interval intracortical inhibition demonstrated “good to excellent” relative reliability (ICC ≥ 0.643). Intracortical facilitation demonstrated the lowest relative reliability (ICC = 0.420–0.908). Corticospinal silent period displayed the lowest absolute reliability (SEm ≤ 18.68%). Good reliability of the maximal compound wave, Hoffman reflex, motor evoked potential, and corticospinal silent period allow for reliable neurological evaluation of peripheral and corticospinal pathways in the vastus medialis. Future research should investigate reliability of the intracortical (short-interval intracortical inhibition and intracortical facilitation) measures by using different paired-pulse stimulus parameters. These findings hold important implications for neurophysiological assessment conducted in the leg extensor group.

Clinical assessment of acute lateral ankle sprain injuries (ROAST): 2019 consensus statement and recommendations of the International Ankle Consortium

Lateral ankle sprain injury is the most common musculoskeletal injury incurred by individuals who participate in sports and recreational physical activities. Following initial injury, a high proportion of individuals develop long-term injury-associated symptoms and chronic ankle instability. The development of chronic ankle instability is consequent on the interaction of mechanical and sensorimotor insufficiencies/impairments that manifest following acute lateral ankle sprain injury. To reduce the propensity for developing chronic ankle instability, clinical assessments should evaluate whether patients in the acute phase following lateral ankle sprain injury exhibit any mechanical and/or sensorimotor impairments. This modified Delphi study was undertaken under the auspices of the executive committee of the International Ankle Consortium. The primary aim was to develop recommendations, based on expert (n=14) consensus, for structured clinical assessment of acute lateral ankle sprain injuries. After two modified Delphi rounds, consensus was achieved on the clinical assessment of acute lateral ankle sprain injuries. Consensus was reached on a minimum standard clinical diagnostic assessment. Key components of this clinical diagnostic assessment include: establishing the mechanism of injury, as well as the assessment of ankle joint bones and ligaments. Through consensus, the expert panel also developed the International Ankle Consortium Rehabilitation-Oriented ASsessmenT (ROAST). The International Ankle Consortium ROAST will help clinicians identify mechanical and/or sensorimotor impairments that are associated with chronic ankle instability. This consensus statement from the International Ankle Consortium aims to be a key resource for clinicians who regularly assess individuals with acute lateral ankle sprain injuries.

National Athletic Trainers' Association position statement: conservative management and prevention of ankle sprains in athletes

OBJECTIVE

To present recommendations for athletic trainers and other allied health care professionals in the conservative management and prevention of ankle sprains in athletes.

BACKGROUND

Because ankle sprains are a common and often disabling injury in athletes, athletic trainers and other sports health care professionals must be able to implement the most current and evidence-supported treatment strategies to ensure safe and rapid return to play. Equally important is initiating preventive measures to mitigate both first-time sprains and the chance of reinjury. Therefore, considerations for appropriate preventive measures (including taping and bracing), initial assessment, both short- and long-term management strategies, return-to-play guidelines, and recommendations for syndesmotic ankle sprains and chronic ankle instability are presented.

RECOMMENDATIONS

The recommendations included in this position statement are intended to provide athletic trainers and other sports health care professionals with guidelines and criteria to deliver the best health care possible for the prevention and management of ankle sprains. An endorsement as to best practice is made whenever evidence supporting the recommendation is available.

Local anaesthetics use does not suppress muscle activity following an ankle injection

PURPOSE

To determine if peroneus longus (PL), peroneus brevis (PB), medial gastrocnemius (MG) and tibialis anterior (TA) muscle activation patterns during inversion perturbation and running tasks are suppressed following lidocaine injection to the anterior talofibular (ATF) and calcaneofibular (CF) ligament regions.

METHODS

Fourteen recreationally active male subjects (age, 24.8 ± 2.9 years; height, 177.0 ± 6.0 cm; mass, 77.7 ± 6.7 kg) participated. Testing was performed under five injection conditions to the ATF and CF regions: 1 ml saline, 1 ml lidocaine, 3 ml saline, 3 ml lidocaine or no injection. Following injection condition, traditional ankle taping was applied. Electromyography patterns of the PL, PB, MG and TA were collected while subjects performed continuous lateral jumps on a custom-built device which elicited an ankle inversion perturbation and treadmill running (3.35 m s(-1), 0.5 % incline).

RESULTS

No significant differences were demonstrated in muscle activation patterns of the PL (n.s.), PB (n.s.), MG (n.s.) or TA (n.s.) for any variable across injected conditions during both tasks. Statistical power was 0.214-0.526 for the PL, 0.087-0.638 for the PB, 0.115-0.560 for the MG and 0.118-0.410 for the TA.

CONCLUSIONS

Injection of lidocaine up to 3 ml to the ATF and CF regions did not suppress muscle activity of the PL, PB, MG or TA during the inversion perturbation or running tasks. Injection up to 3 ml of 1 % lidocaine to the ATF and CF regions may be used without sacrificing the muscle activation patterns about the ankle. This finding is clinically relevant since the use of the injection does not put the patient at any higher risk of reinjury to the site.

Arthrogenic neuromusculature inhibition: a foundational investigation of existence in the hip joint

BACKGROUND

Patients and athletes with diminished gluteal muscle activation are thought to have 'gluteal inhibition'. This may be a component of arthrogenic neuromuscular inhibition, which has been well documented in the knee and generalized to all joints. While clinical evidence surrounding gluteal inhibition increases, supportive research is non-existent. This study investigated whether arthrogenic neuromuscular inhibition occurred about the hip following instillation of intra-articular fluid during functional hip extension tasks.

METHODS

Data was collected in a biomechanics laboratory (control) and hospital setting (intervention). Nine healthy individuals (4M/5F) comprised the control group. The intervention group contained twelve patients (4M/8F) with hip pathology requiring a magnetic resonance arthrogram (capsular distension via intra-articular fluid injection) procedure. The participants performed a pelvic bridge (PB) and active hip extension (EXT) before and after the control time or injection. Peak EMG from the gluteus maximus (GM) was collected bilaterally.

FINDINGS

The findings of this study provide substantial support for arthrogenic inhibition following hip intra-articular fluid instillation during functional tasks. Two-way repeated measures ANOVA revealed a significant group by session interaction effect (PB,EXT: affected/unaffected=0.0192/0.9654 P=0.05, <0.0001/0.0826 P=0.05). Tukey post hoc revealed decreases in ipsilateral peak GM EMG following intervention were significant (0.0238/<0.0001 P=0.025). No changes were observed in the control group.

INTERPRETATION

These concepts are of clinical importance to both patient and athletic populations. Understanding the role of gluteal inhibition in the injury process is essential to the development of rehabilitation and prevention protocols. Restoration and promotion of optimal recruitment patterns are crucial to enhancing athletic performance.

Neuromuscular control and ankle instability

Lateral ankle sprains (LAS) are common injuries in athletics and daily activity. Although most are resolved with conservative treatment, others develop chronic ankle instability (AI)-a condition associated with persistent pain, weakness, and instability-both mechanical (such as ligamentous laxity) and functional (neuromuscular impairment with or without mechanical laxity). The predominant theory in AI is one of articular deafferentation from the injury, affecting closed-loop (feedback/reflexive) neuromuscular control, but recent research has called that theory into question. A considerable amount of attention has been directed toward understanding the underlying causes of this pathology; however, little is known concerning the neuromuscular mechanisms behind the development of AI. The purpose of this review is to summarize the available literature on neuromuscular control in uninjured individuals and individuals with AI. Based on available research and reasonable speculation, it seems that open-loop (feedforward/anticipatory) neuromuscular control may be more important for the maintenance of dynamic joint stability than closed-loop control systems that rely primarily on proprioception. Therefore, incorporating perturbation activities into patient rehabilitation schemes may be of some benefit in enhancing these open-loop control mechanisms. Despite the amount of research conducted in this area, analysis of individuals with AI during dynamic conditions is limited. Future work should aim to evaluate dynamic perturbations in individuals with AI, as well as subjects who have a history of at least one LAS and never experienced recurrent symptoms. These potential findings may help elucidate some compensatory mechanisms, or more appropriate neuromuscular control strategies after an LAS event, thus laying the groundwork for future intervention studies that can attempt to reduce the incidence and severity of acute and chronic lateral ankle injury.

Peroneal activation deficits in persons with functional ankle instability

BACKGROUND

Functional ankle instability (FAI) may be prevalent in as many as 40% of patients after acute lateral ankle sprain. Altered afference resulting from damaged mechanoreceptors after an ankle sprain may lead to reflex inhibition of surrounding joint musculature. This activation deficit, referred to as arthrogenic muscle inhibition (AMI), may be the underlying cause of FAI. Incomplete activation could prevent adequate control of the ankle joint, leading to repeated episodes of instability.

HYPOTHESIS

Arthrogenic muscle inhibition is present in the peroneal musculature of functionally unstable ankles and is related to dynamic peroneal muscle activity.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Twenty-one (18 female, 3 male) patients with unilateral FAI and 21 (18 female, 3 male) uninjured, matched controls participated in this study. Peroneal maximum H-reflexes and M-waves were recorded bilaterally to establish the presence or absence of AMI, while electromyography (EMG) recorded as patients underwent a sudden ankle inversion perturbation during walking was used to quantify dynamic activation. The H:M ratio and average EMG amplitudes were calculated and used in data analyses. Two-way analyses of variance were used to compare limbs and groups. A regression analysis was conducted to examine the association between the H:M ratio and the EMG amplitudes.

RESULTS

The FAI patients had larger peroneal H:M ratios in their nonpathological ankle (0.399 +/- 0.185) than in their pathological ankle (0.323 +/- 0.161) (P = .036), while no differences were noted between the ankles of the controls (0.442 +/- 0.176 and 0.425 +/- 0.180). The FAI patients also exhibited lower EMG after inversion perturbation in their pathological ankle (1.7 +/- 1.3) than in their uninjured ankle (EMG, 3.3 +/- 3.1) (P < .001), while no differences between legs were noted for controls (P > .05). No significant relationship was found between the peroneal H:M ratio and peroneal EMG (P > .05).

CONCLUSION

Arthrogenic muscle inhibition is present in the peroneal musculature of persons with FAI but is not related to dynamic muscle activation as measured by peroneal EMG amplitude. Reversing AMI may not assist in protecting the ankle from further episodes of instability; however dynamic muscle activation (as measured by peroneal EMG amplitude) should be restored to maximize ankle stabilization. Dynamic peroneal activity is impaired in functionally unstable ankles, which may contribute to recurrent joint instability and may leave the ankle vulnerable to injurious loads.

Quadriceps inhibition induced by an experimental knee joint effusion affects knee joint mechanics during a single-legged drop landing

BACKGROUND

Arthrogenic quadriceps muscle inhibition accompanies knee joint effusion and impedes rehabilitation after knee joint injury.

HYPOTHESIS

We hypothesized that an experimentally induced knee joint effusion would cause arthrogenic quadriceps muscle inhibition and lead to increased ground reaction forces, as well as sagittal plane knee angles and moments, during a single-legged drop landing.

STUDY DESIGN

Controlled laboratory study.

METHODS

Nine subjects (4 women and 5 men) underwent 4 conditions (no effusion, lidocaine injection, "low" effusion [30 mL], and "high" effusion [60 mL]) and then performed a single-legged drop landing. Lower extremity muscle activity, peak sagittal plane knee flexion angles, net sagittal plane knee moments, and peak ground reaction forces were measured.

RESULTS

Vastus medialis and lateralis activity were decreased during the low and high effusion conditions (P < .05). However, increases in peak ground reaction forces and decreases in peak knee flexion angle and net knee extension moments occurred only during the high effusion condition (P < .05).

CONCLUSIONS

Knee joint effusion induced quadriceps inhibition and altered knee joint mechanics during a landing task. Subjects landed with larger ground reaction forces and in greater knee extension, thereby suggesting that more force will be transferred to the knee joint and its passive restraints when quadriceps inhibition is present.

CLINICAL RELEVANCE

Knee joint effusion results in arthrogenic quadriceps muscle inhibition, increasing loading about the knee that may potentially increase the risk of future knee joint trauma or degeneration.

Movement discrimination after intra-articular local anaesthetic of the ankle joint

BACKGROUND

The effect on clinical safety of dampening articular mechanoreceptor feedback at the ankle is unknown. Injection of the ankle joint for pain control may result in such dampening. Athletes receiving intra-articular local anaesthetic may therefore be at increased risk of sustaining ankle injuries, which are a common reason for missed sporting participation.

OBJECTIVE

To determine the effect of intra-articular local anaesthetic on movement discrimination at the ankle joint.

DESIGN

Prospective, randomised, double-blinded, placebo-controlled, cross-over trial.

SETTING

Australian Institute of Sport Medical Centre, Canberra, Australia.

PATIENTS

Twenty two healthy subjects (44 ankles) aged 18-26 were recruited for the three visits of the study.

INTERVENTIONS

Subjects were tested for their initial movement discrimination scores using the active movement extent discrimination apparatus (AMEDA). They then received ultrasound-guided intra-articular injections of local anaesthetic (2% lignocaine hydrochloride) or normal saline, on two separate later occasions, before further AMEDA assessment.

MAIN OUTCOME MEASURES

Change in movement discrimination scores after intra-articular injection of local anaesthetic or saline.

RESULTS

Movement discrimination scores were not significantly different from control ankles after injection of either local anaesthetic or saline into the ankle joint.

CONCLUSIONS

The intra-articular injection of neither 2 ml lignocaine nor an equivalent amount of normal saline resulted in significant effects on movement discrimination at the ankle joint. These results suggest that injections of local anaesthetic into the ankle joint are unlikely to significantly affect proprioception and thereby increase injury risk.

Modulation of soleus H-reflex by presynaptic spinal mechanisms during varying surface and ankle brace conditions

AIMS

Reflex excitability is modulated in part by presynaptic spinal mechanisms. Presynaptic inhibition may prevent an over-response of the motoneuron pool to afferent information. A paired-reflex depression (PRD) conditioning protocol can be used to monitor reflex plasticity. Manipulation of stance, surface, and external bracing are common methods of rehabilitating and treating lower extremity musculoskeletal injuries. The intent of this study was to evaluate changes in PRD of the soleus H-reflex during single-leg stance under varying stability conditions.

METHODS

Seven trials were completed for each condition in ten healthy volunteers (age=23+/-1.8 yr, weight 65.0+/-11.3 kg, height=168.7+/-28.0 cm). The conditioning stimuli were composed of soleus H-reflex pairs evoked 80 ms apart at an equal intensity. The mean percent decrease of the second H-reflex relative to the first represented PRD.

RESULTS

A 2 x 2 repeated measures ANOVA (P<0.05) was used to evaluate influence of surface (foam, no foam) and support (semi-rigid ankle brace, no ankle brace) on PRD. Main effects testing revealed a significantly greater soleus PRD (P=.034) for the foam surface (62.5%) compared the flat surface (57.5%). Ankle brace application did not influence soleus PRD (P=0.63).

CONCLUSION

The increase in soleus PRD during the foam condition suggests depression of the motoneuron pool. This may lessen postural over-corrections while maintaining upright stance during less stable conditions. No change in PRD during the ankle brace condition suggests that mechanical reinforcement provided an increase in ankle stability, decreasing the demand on the motoneuron pool.

Arthrogenic muscle inhibition in the leg muscles of subjects exhibiting functional ankle instability

BACKGROUND

Functional ankle instability or a subjective report of ;;giving way'' at the ankle may be present in up to 40% of patients after a lateral ankle sprain. Damage to mechanoreceptors within the lateral ankle ligaments after injury is hypothesized to interrupt neurologic feedback mechanisms resulting in functional ankle instability. The altered input can lead to weakness of muscles surrounding a joint, or arthrogenic muscle inhibition. Arthrogenic muscle inhibition may be the underlying cause of functional ankle instability. Establishing the involvement of arthrogenic muscle inhibition in functional ankle instability is critical to understanding the underlying mechanisms or chronic ankle instability. The purpose of this investigation was to determine if arthrogenic muscle inhibition is present in the ankle joint musculature of patients exhibiting unilateral functional ankle instability.

METHODS

Twenty-nine subjects, 15 with unilateral functional ankle instability and 14 healthy control subjects, consented to participate. Bilateral soleus, peroneal, and tibialis anterior H-reflex and M-wave recruitment curves were obtained. Maximal H-reflex and maximal M-wave values were identified and the H:M ratios were calculated for data analysis. Separate 1 x 2 ANOVA were done for both the functional ankle instability and control groups to evaluate differences between limbs on the H:M ratios. Bonferroni multiple comparison procedures were used for post hoc comparisons (p < or = 0.05).

RESULTS

The soleus and peroneal H:M ratios for subjects with functional ankle instability were smaller in the injured limb when compared with the uninjured limb (p < 0.05). No limb difference was detected for the tibialis anterior H:M ratio in the functional ankle instability group (p = 0.904). No side-to-side differences were detected for the H:M ratios in patients reporting no history of ankle injury (p > 0.05).

CONCLUSIONS

Depressed H:M ratios in the injured limb suggest that arthrogenic muscle inhibition is present in the ankle musculature of patients exhibiting functional ankle instability. Establishing and using therapeutic techniques to reverse arthrogenic muscle inhibition may reduce the incidence of functional ankle instability.

Relationship between ankle-foot swelling and self-assessed function after ankle sprain

PURPOSE

Decreasing swelling after ankle sprain is a main focus of treatment, as it is believed that swelling is related to function. The purpose of this study was to evaluate the relationship between ankle-foot swelling and self-assessed ankle function in the early period after ankle sprain.

METHODS

Thirty-six individuals were tested for ankle-foot volume and self-assessed ankle function within days of spraining their ankle. Volumetric measurements of the injured and uninjured ankle-foot segment were taken with a foot and ankle volumeter. Stepwise linear regression analysis was performed, with function being the dependent variable, and the following variables included as independent variables: gender, age, body mass index, previous history of sprain in the injured ankle, and the volume difference between the injured and uninjured ankle-foot segment.

RESULTS

None of the independent variables were significantly related to self-assessed function. Pearson's correlation coefficient for the injured minus uninjured ankle-foot volume and self-assessed ankle function was -0.003.

CONCLUSION

The results indicate that there is no relationship between ankle-foot swelling and self-assessed ankle function in the early period after ankle sprain injury.

Detection of Dynamic Stability Deficits in Subjects with Functional Ankle Instability

PURPOSE

To determine which combination of landing protocol and analysis technique would be the most effective at detecting differences in dynamic stability between healthy subjects and subjects with functional ankle instability (FAI).

METHODS

Fifty-eight subjects participated in this investigation: 29 healthy individuals and 29 individuals with FAI. Subjects were assessed during a single test session for time to stabilization (TTS) in the anterior/posterior, medial/lateral, and vertical directions from two protocols: a step down and jump protocol. The step down protocol started with each subject atop a 20-cm-high platform, and the jump protocol started with subjects in a standing position 70 cm from the center of a force plate and required each subject to jump off both legs and touch a designated marker placed at a position equivalent to 50% of the subject's maximum vertical leap. TTS scores in the anterior/posterior, medial/lateral, and vertical direction were compared between group, protocol, and type of analysis.

RESULTS

A significant protocol by analysis by group interaction (F(1,56) = 6.9, P = 0.011) was observed for anterior/posterior TTS. Likewise, protocol by group (F(1,56) = 4.4, P = 0.042) and protocol by analysis (F(1,56) = 14.1, P < 0.001) interactions were also noted in anterior/posterior TTS. The jump protocol (2381.7 +/- 36.5 ms) produced significantly greater TTS scores in the vertical direction than the step protocol (1533.5 +/- 71.8 ms), whereas the unbounded third order polynomial (UTOP) method (2554.4 +/- 68.7 ms) produced significant greater TTS scores as compared with the sequential estimation (SE) method (1360.8 +/- 52.1 ms).

CONCLUSIONS

The jump protocol and UTOP method of analysis are the most effective TTS combination in detecting differences between healthy and FAI groups.