Clinical and magnetic resonance imaging outcomes following platelet rich plasma injection for chronic midsubstance Achilles tendinopathy.

BACKGROUND: The successful treatment of chronic mid-substance Achilles tendinopathy remains elusive. Approximately 25% to 50% of patients fail conservative treatment modalities. Scientific evidence has supported the use of platelet rich plasma (PRP) in the tendon healing process, however despite initial promise there is a paucity of clinical data to validate a role for PRP in the treatment of tendon disorders including chronic midsubstance Achilles tendinopathy. METHODS: As an alternative to operative treatment, our practice offers patients with chronic midsubstance Achilles tendinopathy intratendinous injection of PRP. We retrospectively reviewed all patients treated for Achilles tendinopathy with PRP injection over a 2-year period. Baseline and post injection functional scores including the Foot and Ankle Ability Measure (FAAM), Foot and Ankle Ability Measure - Sports (FAAMS), and the Short Form health survey (SF-8) were examined. Patients also underwent post-injection magnetic resonance imaging (MRI), which were compared to available pre-injection MRI data. RESULTS: Ten patients were identified for this study. Pre- and postinjection functional outcome scores were available for eight of ten patients. The average SF-8 score improved from 24.9 to 30.0, the average FAAM score improved from 55.4 to 65.8, and the average FAAMS score improved from 14.8 to 17.4. Complete MRI data was available for six patients. Only one in six Achilles tendons demonstrated qualitative MRI improvement post-injection. CONCLUSION: Patients who received PRP injection demonstrated modest improvement in functional outcome measures, however MRI appearance of diseased Achilles tendons remained largely unchanged following PRP injection.

Salter-Harris type III fractures of the distal femur: plain radiographs can be deceptive.

BACKGROUND: Salter-Harris (SH) III fractures of the distal femur, although rare, can have devastating effects. The purposes of this study were to: (1) compare the intra-articular fracture displacement measured on plain x-ray and magnetic resonance imaging (MRI) or computed tomography (CT) scan and (2) report the outcomes of patients with a SH III fracture of the distal femur. METHODS: All SH III distal femur fractures treated at a large Children's Hospital with a Level I Pediatric Trauma Center between 1995 and 2006 were retrospectively reviewed. A total of 14 patients (average age: 13 y, 11 mo; range: 7 y, 8 mo to 17 y, 11 mo) with an average follow-up time of 21.50 months (range: 2 to 47 mo) were included in this study. Fracture displacement on plain x-ray was compared with the fracture displacement measured on MRI or CT scan. The average time between the initial plain x-ray and MRI or CT scan was 37.48 days (range: 3 h to 6 mo). RESULTS: Plain x-rays significantly underestimated the displacement of SH III fractures versus MRI or CT scan. Six patients who had both plain x-ray and MRI or CT scan had a measured displacement of 0.42 mm and 2.70 mm, respectively (paired Student t test, P=0.005). Ten of the 14 patients (71%) had no physical limitations and full knee motion at their most recent follow-up visit. The treatment of 4 patients (29%) was changed based on the findings of the additional MRI or CT scan. CONCLUSIONS: This study and earlier studies have shown a high rate of poor results with SH III fractures of the distal femur. This type of fracture pattern is extremely unstable and the true displacement is often underestimated by x-rays. Thus, it is strongly recommended that an MRI or CT scan be obtained on every SH III fracture of the distal femur. Moreover, any SH III fracture visible on plain radiographs should be treated with open reduction, internal fixation. LEVEL OF EVIDENCE: Level IV.

Low incidence of postoperative complications due to pin placement in computer-navigated total knee arthroplasty.

Computer-navigated joint arthroplasty surgery using optical tracking systems requires arrays fixated to bone via pins. Reports of fractures at pin sites have raised concern about safety. We reviewed the postoperative complications occurring in a single-surgeon series of 984 consecutive primary total knee arthroplasties. All pins were placed unicortically and connected by a dual pin array. Femoral pins were placed into the medial epicondyle, and tibial pins were placed in the shaft 10 cm inferior to the joint line. There were no fractures. Seventeen (1.7%) patients had minor pin-related complications. Twelve patients had a superficial infection around the tibial pin sites, which resolved with antibiotics. None of the infections required readmission or reoperation. We believe pin placement to be safe and effective with proper technique.