Citations

Snapping pes anserinus syndrome is an often encountered cause of medial knee snapping. It results from impingement and translation of the gracilis tendon or semitendinosus tendon over the osseous structures of the knee during active flexion and extension. Ultrasonography is often the diagnostic imaging test of choice in cases of mechanical snapping. We report 2 cases of painful snapping pes anserinus and highlight the value of dynamic ultrasound in making an accurate diagnosis so as to direct care.

Background: Bone marrow aspirate concentrate (BMAC) is increasingly used as a regenerative therapy for musculoskeletal pathological conditions despite limited evidence-based support. Hypothesis: BMAC will prove feasible, safe, and efficacious for the treatment of pain due to mild to moderate degenerative joint disease of the knee. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: In this prospective, single-blind, placebo-controlled trial, 25 patients with bilateral knee pain from bilateral osteoarthritis were randomized to receive BMAC into one knee and saline placebo into the other. Fifty-two milliliters of bone marrow was aspirated from the iliac crests and concentrated in an automated centrifuge. The resulting BMAC was combined with platelet-poor plasma for an injection into the arthritic knee and was compared with a saline injection into the contralateral knee, thereby utilizing each patient as his or her own control. Safety outcomes, pain relief, and function as measured by Osteoarthritis Research Society International (OARSI) measures and the visual analog scale (VAS) score were tracked initially at 1 week, 3 months, and 6 months after the procedure. Results: There were no serious adverse events from the BMAC procedure. OARSI Intermittent and Constant Osteoarthritis Pain and VAS pain scores in both knees decreased significantly from baseline at 1 week, 3 months, and 6 months ( P ≤ .019 for all). Pain relief, although dramatic, did not differ significantly between treated knees ( P > .09 for all). Conclusion: Early results show that BMAC is safe to use and is a reliable and viable cellular product. Study patients experienced a similar relief of pain in both BMAC- and saline-treated arthritic knees. Further study is required to determine the mechanisms of action, duration of efficacy, optimal frequency of treatments, and regenerative potential. Registration: ClinicalTrials.gov record 12-004459.

The main objective of this pictorial essay is to illustrate the sonographic appearance of the postoperative carpal tunnel and median nerve. Carpal tunnel surgical treatment failures have been shown to occur in up to 19% of a large series requiring re-exploration. Surgical management options for recurrent carpal tunnel syndrome (CTS) include revision release, neurolysis, vein wrapping, and fat grafting procedures. While several descriptions of median nerve entrapment in CTS exist in the ultrasound literature, little is written regarding its postoperative appearance. We report the sonographic changes in the appearance of the median nerve and postoperative carpal tunnel.

Background: Prior reports on metabolic derangements observed in distance running frequently have small sample sizes, lack prerace laboratory measures, and report sodium as the sole measure. Hypothesis: Metabolic abnormalities—hyponatremia, hypokalemia, renal dysfunction, hemoconcentration—are frequent after completing a full or half marathon. Clinically significant changes occur in these laboratory values after race completion. Study Design: Observational, cross-sectional study. Methods: Consenting marathon and half marathon racers completed a survey as well as finger stick blood sampling on race day of the National Marathon to Fight Breast Cancer (Jacksonville, Florida, February 2008). Parallel blood measures were obtained before and after race completion (prerace, n = 161; postrace, n = 195). Results: The prevalence of prerace and postrace hyponatremia was 8 of 161 (5.0%) and 16 of 195 (8.2%), respectively. Hypokalemia was not present prerace but was present in 1 runner postrace (1 of 195). Renal dysfunction occurred prerace in 14 of 161 (8.7%) and postrace in 83 of 195 (42.6%). Among those with postrace renal dysfunction, 45.8% (38 of 83) were classified as moderate or severe. Hemoconcentration was present in 2 of 161 (1.2%) prerace and 6 of 195 (3.1%) postrace. The mean changes in laboratory values were (postrace minus prerace): sodium, 1.6 mmol/L; potassium, −0.2 mmol/L; blood urea nitrogen, 2.8 mg/dL; creatinine, 0.2 mg/dL; and hemoglobin, 0.3 g/dL for 149 pairs (except blood urea nitrogen, n = 147 pairs). Changes were significant for all comparisons ( P < 0.01) except potassium ( P = 0.08) and hemoglobin ( P = 0.01). Conclusions: Metabolic abnormalities are common among endurance racers, and they may be present prerace, including hyponatremia. The clinical significance of these findings is unknown. Clinical relevance: It is unclear which runners are at risk for developing clinically important metabolic derangements. Participating in prolonged endurance exercise appears to be safe in the majority of racers.

Background: Posterior tibial tendon dysfunction (PTTD) is a common malady leading to acquired flatfoot, which frequently causes foot and ankle pain and swelling. We hypothesized that patients with PTTD and pitting edema along the course of the posterior tibial tendon (PTT) would have evidence of fluid within the tendon sheath on MRI. We introduce and validate a novel, yet simple physical examination finding, the posterior tibial edema (PTE) sign, to help distinguish PTTD from other causes of foot and ankle pain and swelling. Patients and Methods: To determine an association between the PTE sign and changes to the PTT evident on MRI, we reviewed the medical records of patients with PTTD who underwent magnetic resonance imaging (MRI). Results: Of 186 patients identified with PTTD, 49 underwent MRI, and 42 (86%) demonstrated imaging characteristics consistent with tendonitis, tendinosis, or tenosynovitis. Presence or absence of increased posterior malleolar pitting edema agreed with presence or absence of these MRI findings in 43 patients (88%), making the clinical examination finding significantly predictive of MRI results ( p = 0.01). The sensitivity of the test for PTE was 86%, with specificity of 100%. Conclusion: The PTE sign refers to pitting edema along the course of the PTT, not associated with acute trauma and not accompanied by other areas of edema. Physical examination signs that are highly sensitive and specific to the condition may help lower the cost of diagnosis by eliminating the need for expensive tests that are not always necessary.

Background: Subtalar arthrodesis is a common procedure for treating subtalar arthrosis. An isolated lateral incision can be used as an approach to subtalar fusion alone. However, it can be a difficult approach for correction of varus or valgus hindfoot deformities through the subtalar joint; especially if it involves distraction to correct calcaneal alignment. Less commonly, two-incision or single-incision medial approaches also have been described, but distraction and angular correction can still be difficult. We present an alternative method, using a posterior Achilles tendon-splitting procedure, that gives excellent subtalar exposure and the ability to obtain distraction with angular correction and bone grafting. Materials and Methods: Six consecutive patients underwent subtalar fusion with a posterior approach. Both varus and valgus deformities secondary to trauma, tendon insufficiency, or congenital deformities were corrected. Distraction was accomplished with laminar spreaders, and fixation was obtained with two 7.3-mm partially threaded cannulated screws. All patients were followed until fusion, and clinical and radiographic results were recorded. No other concomitant procedures were performed. Results: Fusion was observed radiographically in all patients by 3 months postoperatively. No serious wound complications occurred. Correction to slightly valgus alignment (for varus deformity) or neutral alignment (for valgus deformity) was obtained without collapse of autologous bone graft. Talocalcaneal height and all angular measurements were significantly increased (all p < 0.05). Conclusion: The posterior approach for distraction arthrodesis is an alternative to the standard lateral approach technique. It allows safe exposure with the ability to distract while also correcting varus or valgus deformity of the subtalar joint.