Lesser Metatarsophalangeal Joint Plantar Plate Degeneration and Tear and Acute First Metatarsophalangeal Joint Capsuloligamentous Injury: What the Surgeon Wants to Know.

Injuries to the plantar plate complex of the first toe and the lesser toes, although closely related anatomically, differ significantly in their pathogenesis. Lesser metatarsophalangeal joint plantar plate degeneration and tear typically presents as an attritional pattern of capsuloligamentous deficiency in middle-aged patients, whereas first metatarsophalangeal joint capsuloligamentous injury is typically acute and occurs in younger adult athletes engaged in sports involving repetitive running and jumping. Consequently, considerations regarding surgical decision-making also differ. Knowledge of the anatomy, pathophysiological basis, common patterns, grading and classification of these injuries, and indications for surgery, will aid imaging interpretation in the preoperative setting. The acuity and extent of injury, tissue quality and functional requirements of the patient (such as timely return to sport) influence clinical decision-making with respect to conservative versus surgical management and are informed by the use of optimized multimodal imaging. This section will provide an overview of these injuries in 2 parts, separated into those affecting the first toe and the lesser toes, and will highlight imaging findings relevant to surgical decision-making.

Combined femoral and acetabular version and synovitis are associated with dGEMRIC scores in people with femoroacetabular impingement (FAI) syndrome.

This study sought to explore, in people with symptoms, signs and imaging findings of femoroacetabular impingement (FAI syndrome): (1) whether more severe labral damage, synovitis, bone marrow lesions, or subchondral cysts assessed on magnetic resonance imaging (MRI) were associated with poorer cartilage health, and (2) whether abnormal femoral, acetabular, and/or combined femoral and acetabular versions were associated with poorer cartilage health. This cross-sectional study used baseline data from the 50 participants with FAI syndrome in the Australian FASHIoN trial (ACTRN12615001177549) with available dGEMRIC scans. Cartilage health was measured using delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score sampled at the chondrolabral junction on three midsagittal slices, at one acetabular and one femoral head region of interest on each slice, and MRI features were assessed using the Hip Osteoarthritis MRI Score. Analyses were adjusted for alpha angle and body mass index, which are known to affect dGEMRIC score. Linear regression assessed the relationship with the dGEMRIC score of (i) selected MRI features, and (ii) femoral, acetabular, and combined femoral and acetabular versions. Hips with more severe synovitis had worse dGEMRIC scores (partial η2 = 0.167, p = 0.020), whereas other MRI features were not associated. A lower combined femoral and acetabular version was associated with a better dGEMRIC score (partial η2 = 0.164, p = 0.021), whereas isolated measures of femoral and acetabular version were not associated. In conclusion, worse synovitis was associated with poorer cartilage health, suggesting synovium and cartilage may be linked to the pathogenesis of FAI syndrome. A lower combined femoral and acetabular version appears to be protective of cartilage health at the chondrolabral junction.

Do patients with femoroacetabular impingement syndrome who undergo hip arthroscopy display improved alpha angle (magnetic resonance imaging) and radiographic hip morphology?

AIMS: To compare (a) the change in radiological bony morphology between participants with femoroacetabular impingement (FAI) syndrome who underwent arthroscopic hip surgery compared to physiotherapist-led non-surgical care and (b) the change in radiological bony morphology between participants with FAI syndrome who underwent arthroscopic hip surgery involving cam resection or acetabular rim trimming or combined cam resection and acetabular rim trimming. METHODS: Maximum alpha angle measurements on magnetic resonance imaging and Hip2 Norm standardized hip measurements on radiographs were recorded at baseline and at 12 months postoperatively. One-way analysis of covariance and independent T tests were conducted between participants who underwent arthroscopic hip surgery and physiotherapist-led non-surgical care. Independent T tests and analysis of variance were conducted between participants who underwent the 3 different arthroscopic hip procedures. RESULTS: Arthroscopic hip surgery resulted in significant improvements to mean alpha angle measurements (decreased from 70.8° to 62.1°) (P value < .001, 95% CI -11.776, -4.772), lateral center edge angle (LCEA) (P value = .030, 95% CI -3.403, -0.180) and extrusion index (P value = 0.002, 95% CI 0.882, 3.968) compared to physiotherapist-led management. Mean maximum 1-year postoperative alpha angle was 59.0° (P value = .003, 95% CI 4.845, 18.768) for participants who underwent isolated cam resection. Measurements comparing the 3 different arthroscopic hip procedures only differed in total femoral head coverage (F[2,37] = 3.470, P = .042). CONCLUSION: Arthroscopic hip surgery resulted in statistically significant improvements to LCEA, extrusion index and alpha angle as compared to physiotherapist-led management. Measured outcomes between participants who underwent cam resection and/or acetabular rim trimming only differed in total femoral head coverage.

Moderators, Mediators, and Prognostic Indicators of Treatment With Hip Arthroscopy or Physical Therapy for Femoroacetabular Impingement Syndrome: Secondary Analyses From the Australian FASHIoN Trial.

BACKGROUND: Although randomized controlled trials comparing hip arthroscopy with physical therapy for the treatment of femoroacetabular impingement (FAI) syndrome have emerged, no studies have investigated potential moderators or mediators of change in hip-related quality of life. PURPOSE: To explore potential moderators, mediators, and prognostic indicators of the effect of hip arthroscopy and physical therapy on change in 33-item international Hip Outcome Tool (iHOT-33) score for FAI syndrome. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Overall, 99 participants were recruited from the clinics of orthopaedic surgeons and randomly allocated to treatment with hip arthroscopy or physical therapy. Change in iHOT-33 score from baseline to 12 months was the dependent outcome for analyses of moderators, mediators, and prognostic indicators. Variables investigated as potential moderators/prognostic indicators were demographic variables, symptom duration, alpha angle, lateral center-edge angle (LCEA), Hip Osteoarthritis MRI Scoring System (HOAMS) for selected magnetic resonance imaging (MRI) features, and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score. Potential mediators investigated were change in chosen bony morphology measures, HOAMS, and dGEMRIC score from baseline to 12 months. For hip arthroscopy, intraoperative procedures performed (femoral ostectomy ± acetabular ostectomy ± labral repair ± ligamentum teres debridement) and quality of surgery graded by a blinded surgical review panel were investigated for potential association with iHOT-33 change. For physical therapy, fidelity to the physical therapy program was investigated for potential association with iHOT-33 change. RESULTS: A total of 81 participants were included in the final moderator/prognostic indicator analysis and 85 participants in the final mediator analysis after exclusion of those with missing data. No significant moderators or mediators of change in iHOT-33 score from baseline to 12 months were identified. Patients with smaller baseline LCEA (ß = -0.82; P = .034), access to private health care (ß = 12.91; P = .013), and worse baseline iHOT-33 score (ß = -0.48; P < .001) had greater iHOT-33 improvement from baseline to 12 months, irrespective of treatment allocation, and thus were prognostic indicators of treatment response. Unsatisfactory treatment fidelity was associated with worse treatment response (ß = -24.27; P = .013) for physical therapy. The quality of surgery and procedures performed were not associated with iHOT-33 change for hip arthroscopy (P = .460-.665 and P = .096-.824, respectively). CONCLUSION: No moderators or mediators of change in hip-related quality of life were identified for treatment of FAI syndrome with hip arthroscopy or physical therapy in these exploratory analyses. Patients who accessed the Australian private health care system, had smaller LCEAs, and had worse baseline iHOT-33 scores, experienced greater iHOT-33 improvement, irrespective of treatment allocation.

Multi-centre randomised controlled trial comparing arthroscopic hip surgery to physiotherapist-led care for femoroacetabular impingement (FAI) syndrome on hip cartilage metabolism: the Australian FASHIoN trial.

BACKGROUND: Arthroscopic surgery for femoroacetabular impingement syndrome (FAI) is known to lead to self-reported symptom improvement. In the context of surgical interventions with known contextual effects and no true sham comparator trials, it is important to ascertain outcomes that are less susceptible to placebo effects. The primary aim of this trial was to determine if study participants with FAI who have hip arthroscopy demonstrate greater improvements in delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) index between baseline and 12 months, compared to participants who undergo physiotherapist-led management. METHODS: Multi-centre, pragmatic, two-arm superiority randomised controlled trial comparing physiotherapist-led management to hip arthroscopy for FAI. FAI participants were recruited from participating orthopaedic surgeons clinics, and randomly allocated to receive either physiotherapist-led conservative care or surgery. The surgical intervention was arthroscopic FAI surgery. The physiotherapist-led conservative management was an individualised physiotherapy program, named Personalised Hip Therapy (PHT). The primary outcome measure was change in dGEMRIC score between baseline and 12 months. Secondary outcomes included a range of patient-reported outcomes and structural measures relevant to FAI pathoanatomy and hip osteoarthritis development. Interventions were compared by intention-to-treat analysis. RESULTS: Ninety-nine participants were recruited, of mean age 33 years and 58% male. Primary outcome data were available for 53 participants (27 in surgical group, 26 in PHT). The adjusted group difference in change at 12 months in dGEMRIC was -59 ms (95%CI - 137.9 to - 19.6) (p = 0.14) favouring PHT. Hip-related quality of life (iHOT-33) showed improvements in both groups with the adjusted between-group difference at 12 months showing a statistically and clinically important improvement in arthroscopy of 14 units (95% CI 5.6 to 23.9) (p = 0.003). CONCLUSION: The primary outcome of dGEMRIC showed no statistically significant difference between PHT and arthroscopic hip surgery at 12 months of follow-up. Patients treated with surgery reported greater benefits in symptoms at 12 months compared to PHT, but these benefits are not explained by better hip cartilage metabolism. TRIAL REGISTRATION DETAILS: Australia New Zealand Clinical Trials Registry reference: ACTRN12615001177549 . Trial registered 2/11/2015.

Protocol for a multi-centre randomised controlled trial comparing arthroscopic hip surgery to physiotherapy-led care for femoroacetabular impingement (FAI): the Australian FASHIoN trial.

BACKGROUND: Femoroacetabular impingement syndrome (FAI), a hip disorder affecting active young adults, is believed to be a leading cause of hip osteoarthritis (OA). Current management approaches for FAI include arthroscopic hip surgery and physiotherapy-led non-surgical care; however, there is a paucity of clinical trial evidence comparing these approaches. In particular, it is unknown whether these management approaches modify the future risk of developing hip OA. The primary objective of this randomised controlled trial is to determine if participants with FAI who undergo hip arthroscopy have greater improvements in hip cartilage health, as demonstrated by changes in delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) index between baseline and 12 months, compared to those who undergo physiotherapy-led non-surgical management. METHODS: This is a pragmatic, multi-centre, two-arm superiority randomised controlled trial comparing hip arthroscopy to physiotherapy-led management for FAI. A total of 140 participants with FAI will be recruited from the clinics of participating orthopaedic surgeons, and randomly allocated to receive either surgery or physiotherapy-led non-surgical care. The surgical intervention involves arthroscopic FAI surgery from one of eight orthopaedic surgeons specialising in this field, located in three different Australian cities. The physiotherapy-led non-surgical management is an individualised physiotherapy program, named Personalised Hip Therapy (PHT), developed by a panel to represent the best non-operative care for FAI. It entails at least six individual physiotherapy sessions over 12 weeks, and up to ten sessions over six months, provided by experienced musculoskeletal physiotherapists trained to deliver the PHT program. The primary outcome measure is the change in dGEMRIC score of a ROI containing both acetabular and femoral head cartilages at the chondrolabral transitional zone of the mid-sagittal plane between baseline and 12 months. Secondary outcomes include patient-reported outcomes and several structural and biomechanical measures relevant to the pathogenesis of FAI and development of hip OA. Interventions will be compared by intention-to-treat analysis. DISCUSSION: The findings will help determine whether hip arthroscopy or an individualised physiotherapy program is superior for the management of FAI, including for the prevention of hip OA. TRIAL REGISTRATION: Australia New Zealand Clinical Trials Registry reference: ACTRN12615001177549 . Trial registered 2/11/2015 (retrospectively registered).

Imaging of Lesser Metatarsophalangeal Joint Plantar Plate Degeneration, Tear, and Repair.

Plantar plate degeneration and tear is a common cause of forefoot pain, typically involving the second metatarsophalangeal joint at the proximal phalangeal insertion laterally, frequently confused with the second web space Morton neuroma. The condition has received increased attention with the development of surgical techniques that can result in successful repair of the plantar plate and substantial improvement in patient symptoms. High-resolution MRI or ultrasound can confirm a diagnosis of plantar plate degeneration and tear and exclude other pathologies, particularly Morton neuroma. The normal plantar plate is a mildly hyperechoic structure on ultrasound and is hypointense on all conventional MR sequences. Plantar plate degeneration manifests on ultrasound as hypoechoic echotextural change and on MRI as mild signal hyperintensity on short TE sequences, becoming less conspicuous on long TE sequences. Adjacent entheseal bony irregularity is commonly present. Plantar plate tears on ultrasound may be seen as an anechoic cleft defect or area of heterogeneous echotexture, sometimes more conspicuous with dorsiflexion stress. Plantar plate tears demonstrate greater signal hyperintensity on proton-density sequences, becoming more conspicuous on fat-suppressed proton density and T2-weighted sequences. Edema and fibrotic change in the pericapsular fat plane is commonly seen in the setting of an adjacent plantar plate tear and should not be misinterpreted as reflecting a Morton neuroma.

Randomized controlled trial of osteoconductive fixation screws for anterior cruciate ligament reconstruction: a comparison of the Calaxo and Milagro screws.

PURPOSE: To compare the outcome of 2 bioabsorbable screws for tibial interference fixation in anterior cruciate ligament reconstruction with reference to rate of absorption, osteoconductive properties, and clinical outcome. METHODS: Patients undergoing primary anterior cruciate ligament reconstruction with hamstring autograft in a single unit were invited to participate in this study. Patients were randomized to receive either the Calaxo screw (Smith & Nephew, Andover, MA) or Milagro screw (DePuy Mitek, Raynham, MA) for tibial fixation. Patients were reviewed with subjective and objective evaluation by use of the International Knee Documentation Committee form, Lysholm score, KT-1000 arthrometry (MEDmetric, San Diego, CA), and clinical examination. Magnetic resonance imaging was performed at 1 year and computed tomography scanning at 1 week and at 6, 12, and 24 months. RESULTS: Sixty patients agreed to participate in the study, with 32 patients randomized to the Calaxo screw and 28 to the Milagro screw for tibial fixation. There was no significant difference in subjective or objective clinical outcome between the 2 groups. At 24 months, 88% of Calaxo screws showed complete screw resorption compared with 0% of Milagro screws (P < .001). Tibial cysts were present in 88% of the Calaxo group and 7% of the Milagro group (P = .001). At 24 months, the mean volume of new bone formation for the Calaxo group was 21% of original screw volume. Ossification of the Milagro screw was unable to be accurately assessed as a result of incomplete screw resorption. CONCLUSIONS: Both screws showed similar favorable objective and subjective outcomes at 2 years. The Calaxo screw resorbed completely over a period of 6 months and was associated with a high incidence of intra-tunnel cyst formation. The Milagro screw increased in volume over a period of 6 months, followed by a gradual resorption, which was still ongoing at 2 years. Both screws were associated with tunnel widening, and neither showed evidence of significant tunnel ossification. We conclude that, despite satisfactory clinical outcomes, the addition of "osteoconductive" materials to bioabsorbable screws is not associated with bone formation at the screw site at 2 years. LEVEL OF EVIDENCE: Level I, randomized controlled trial.

Imaging findings in arthrofibrosis of the ankle and foot.

Arthrofibrosis is defined as joint pain and stiffness that does not allow functional range of motion and is due to adhesions or contracture of the joint. Arthrofibrosis is characterized by an abnormal proliferation of fibrous tissue that may be focal or diffuse and intra-articular or extra-articular. Trauma and surgery are the most common etiological factors. In the ankle and foot symptomatic arthrofibrosis is not uncommonly seen in the talocrural joint, posterior subtalar joint, and the metatarsophalangeal joints. Imaging can assist with diagnosis and planning treatment, most commonly using MRI and occasionally ultrasound. Typical imaging findings consist of capsular and pericapsular thickening and scarring, best demonstrated on proton-density MR images but also demonstrable on ultrasound.

Imaging of sports injuries in the foot.

OBJECTIVE: This article selectively reviews several areas in which imaging can play a major role in the diagnosis and treatment of sports injuries of the foot. CONCLUSION: Diagnostic imaging provides useful evaluation of capsuloligamentous sports injuries and Morton neuroma in the foot and facilitates appropriate treatment. An understanding of the relevant anatomy, normal imaging appearance, and the spectrum of imaging findings in the setting of injury is important for the practicing radiologist.

Imaging of talar dome chondral and osteochondral lesions.

Talar dome chondral and osteochondral lesions are a common cause of ankle pain and subjective instability. The goal of imaging these lesions is primarily their detection, demonstration of their position and extent, including status of the chondral surface, demonstration of any associated chondral delamination, assessment of the integrity of the subchondral plate, and assessment of the cancellous subchondral bone for bone marrow edema like signal, sclerosis, cystic change, and for the presence of an unstable osteochondral fragment. Although plain radiography, computerized tomography, and bone scan may be helpful in the detection and characterization of these lesions, magnetic resonance imaging is the only imaging modality that will provide a comprehensive assessment of all these issues. Technical aspects of plain radiography, computerized tomography, and magnetic resonance imaging are discussed, and imaging findings are presented.

Imaging of peripheral nerve lesions in the lower limb.

Lower limb peripheral neuropathy may have a variety of causes. This article focuses on focal neural lesions because of neural entrapment associated with static mechanical compression or dynamic compression/stretching. Mechanical compression may relate to direct blunt trauma, surgical injury, mass effect associated with adjacent mass lesions, and frictional effects associated with fibrous bands. Stretching neural injury may be associated with abnormalities in alignment such as plano-valgus hindfoot and hindfoot pronation. Recurrent inversion ankle injuries may also cause neural injury. Neural injury may be associated with denervation of the muscles supplied by the nerve. Electromyography (EMG) remains the gold standard for diagnosis of denervation. Diagnostic imaging plays a complementary role to EMG in difficult cases, the anticoagulated patient, and in clarifying the etiology of an EMG-demonstrated neuropathy. Magnetic resonance imaging and ultrasound can be used in peripheral nerve imaging to demonstrate extrinsic compressive lesions, focal neural lesions such as neural edema and swelling, focal neural scarring (posttraumatic neuroma in continuity) and intraneural ganglia. Imaging can also demonstrate the effects of muscle denervation. Focal areas of tenderness can be highlighted using skin markers for magnetic resonance imaging and by transducer palpation on ultrasound. Ultrasound can be particularly useful in assessing for intrinsic lesions in small peripheral nerves because of the superior spatial resolution of ultrasound in assessing superficial structures. Plain x-rays (and sometimes computed tomography scanning) may show significant bone changes and should be the initial imaging modality.