T1-VIBE and STIR MRI of lumbar pars interarticularis injuries in elite athletes: fracture characterisation and potential prognostic indicators.

OBJECTIVES: To assess how pars interarticularis fracture characteristics on T1-VIBE and STIR MRI relate to healing and identify anatomical parameters that may impact healing. MATERIALS AND METHODS: A retrospective review of an MRI series of lumbar pars interarticularis injuries in elite athletes over a 3-year period. Fracture configurations, signal intensities and anatomical parameters were recorded by two radiologists. Statistical analysis employed multilevel mixed-effects linear regressions, adjusted for repeated measures and baseline covariates. RESULTS: Forty-seven lumbar pars interarticularis injuries among 31 athletes were assessed. On final scans for each athlete, 15% (7/47) injuries had worsened, 23% (11/47) remained stable, 43% (20/47) partially healed and 19% (9/47) healed completely. Healing times varied, quickest was 49 days for a chronic fracture in a footballer. Bone marrow oedema signal was highest in worsened fractures, followed by improved, and lowest in stable fractures. As healing progressed, T1-VIBE signal at the fracture line decreased. Bone marrow oedema and fracture line signal peaked at 90-120 days before decreasing until 210-240 days. Fractures with smaller dimensions, more vertical orientation and a longer superior articular facet beneath were significantly associated with better healing (p < 0.05). CONCLUSION: Most diagnosed athletic pars interarticularis injuries improve. Normalising T1-VIBE signal at the fracture line is a novel measurable indicator of bony healing. Contrastingly, bone marrow oedema signal is higher in active fractures irrespective of healing or deterioration. Injuries initially perceived as worsening may be exhibiting the normal osteoclastic phase of healing. Better outcomes favour smaller, vertical fractures with a longer superior articular facet beneath.

Rupture of the peroneus quartus tendon in a professional rugby player.

The peroneus quartus is one of a variety of described accessory peroneal muscles, most commonly an incidental finding on MRI or ultrasound of the ankle. We present the only described case in the literature of a peroneus quartus tendon rupture in a professional rugby player as well as the MRI findings.

Proximal adductor avulsions are rarely isolated but usually involve injury to the PLAC and pectineus: descriptive MRI findings in 145 athletes.

PURPOSE: The purpose of the study is to review the MRI findings in a cohort of athletes who sustained acute traumatic avulsions of the adductor longus fibrocartilaginous entheses, and to investigate related injuries namely the pyramidalis-anterior pubic ligament-adductor longus complex (PLAC). Associated muscle and soft tissue injuries were also assessed. METHODS: The MRIs were reviewed for a partial or complete avulsion of the adductor longus fibrocartilage, as well as continuity or separation of the adductor longus from the pyramidalis. The presence of a concurrent partial pectineus tear was noted. Demographic data were analysed. Linear and logistic regression was used to examine associations between injuries. RESULTS: The mean age was 32.5 (SD 10.9). The pyramidalis was absent in 3 of 145 patients. 85 of 145 athletes were professional and 52 competed in the football Premier League. 132 had complete avulsions and 13 partial. The adductor longus was in continuity with pyramidalis in 55 athletes, partially separated in seven and completely in 81 athletes. 48 athletes with a PLAC injury had a partial pectineus avulsion. Six types of PLAC injuries patterns were identified. Associated rectus abdominis injuries were rare and only occurred in five patients (3.5%). CONCLUSION: The proximal adductor longus forms part of the PLAC and is rarely an isolated injury. The term PLAC injury is more appropriate term. MRI imaging should assess all the anatomical components of the PLAC post-injury, allowing recognition of the different patterns of injury. LEVEL OF EVIDENCE: Level III.

Revision of metal-on-metal hip arthroplasty in a tertiary center: a prospective study of 39 hips with between 1 and 4 years of follow-up.

BACKGROUND AND PURPOSE: Operative findings during revision of metal-on-metal hip arthroplasty (MOMHA) vary widely and can involve massive soft tissue and bone disruption. As a result, planning of theater time and resources is difficult, surgery is challenging, and outcomes are often poor. We describe our experience with revision of MOMHA and provide recommendations for management. PATIENTS AND METHODS: We present the findings and outcomes of 39 consecutive MOMHAs (in 35 patients) revised in a tertiary unit (median follow-up time 30 (12-54) months). The patients underwent a preoperative work-up including CT, metal artifact reduction sequence (MARS) MRI, and blood metal ion levels. RESULTS: We determined 5 categories of failure. 8 of 39 hips had conventional failure mechanisms including infection and impingement. Of the other 31 hips, 14 showed synovitis without significant disruption of soft tissue; 6 had a cystic pseudotumor with significant soft tissue disruption; 7 had significant osteolysis; and 4 had a solid pseudotumor. Each category of failure had specific surgical hazards that could be addressed preoperatively. There were 2 reoperations and 1 patient (2 hips) died of an unrelated cause. Median Oxford hip score (OHS) was 37 (9-48); median change (ΔOHS) was 17 (-10 to 41) points. ΔOHS was similar in all groups-except those patients with solid pseudotumors and those revised to metal-on-metal bearings, who fared worse. INTERPRETATION: Planning in revision MOMHA is aided by knowledge of the different categories of failure to enable choice of appropriate personnel, theater time, and equipment. With this knowledge, satisfactory outcomes can be achieved in revision of metal-on-metal hip arthroplasty.

Isolated ischaemic contracture of medial head of gastrocnemius.

A 47-year-old woman presented with a disabling fixed flexion deformity of the knee and an equinus deformity of the ankle following treatment in a cast for a minor flexion deformity following a tibial plateau fracture. Two years later, the cause was identified as an isolated ischaemic contracture involving the medial head of gastrocnemius. She made a good recovery following extensive corrective surgery and rehabilitation.

Magnetic resonance imaging findings in painful metal-on-metal hips: a prospective study.

Metal artifact reduction sequence magnetic resonance imaging findings are reported in a prospective series of 31 patients with unexplained painful metal-on-metal (MOM) hips. The abnormalities identified were fluid collection (20 patients), solid mass (2 patients), moderate to severe muscle atrophy (23 patients), and muscle edema (8 patients). In conclusion, soft tissue lesions and muscle atrophy appear to be prevalent in unexplained painful MOM hips. Metal artifact reduction sequence magnetic resonance imaging may be useful to diagnose and monitor at-risk hips but requires validation in well-functioning MOM hips before it can guide clinical decision making.

Embolization of bleeding residual uterine vascular malformations in patients with treated gestational trophoblastic tumors.

PURPOSE: To retrospectively evaluate embolotherapy of bleeding residual uterine vascular malformations in patients with gestational trophoblastic tumors. MATERIALS AND METHODS: Fourteen patients were treated over the past 20 years. Embolizations were performed with a common femoral artery approach. Duplex ultrasonography was performed before and after embolization to document the uterine vascularity. The technique and materials used for each embolization, control of hemorrhage, need for repeat embolization, complications, and outcome of subsequent pregnancies were assessed. RESULTS: Hemorrhage was controlled in 11 of the 14 patients; two patients required hysterectomy and one required uterine artery ligation for failure to control hemorrhage after initial embolization. Six patients required repeat embolization for recurrence of bleeding. Therapeutic benefit and success were associated with the ability to selectively embolize the uterine artery and to achieve a greater than 80% reduction in vascular malformation size. Pulsatility indexes of the uterine arteries and endometrial encroachment were not predictive of recurrent hemorrhage. Two patients delivered a total of three full-term infants, one patient experienced a miscarriage, and another experienced a termination of pregnancy following embolotherapy. Pain requiring opiate analgesia was a frequent complication of treatment. CONCLUSION: Selective uterine artery embolization is a safe and effective treatment for severe bleeding from residual uterine vascular malformations in patients with treated gestational trophoblastic tumors.