Alfred C. Gellhorn

Osteoarthritis of the spine: the facet joints

Osteoarthritis (OA) of the spine involves the facet joints, which are located in the posterior aspect of the vertebral column and, in humans, are the only true synovial joints between adjacent spinal levels. Facet joint osteoarthritis (FJ OA) is widely prevalent in older adults, and is thought to be a common cause of back and neck pain. The prevalence of facet-mediated pain in clinical populations increases with increasing age, suggesting that FJ OA might have a particularly important role in older adults with spinal pain. Nevertheless, to date FJ OA has received far less study than other important OA phenotypes such as knee OA, and other features of spine pathoanatomy such as degenerative disc disease. This Review presents the current state of knowledge of FJ OA, including relevant anatomy, biomechanics, epidemiology, and clinical manifestations. We present the view that the modern concept of FJ OA is consonant with the concept of OA as a failure of the whole joint, and not simply of facet joint cartilage.

Management Patterns in Acute Low Back Pain: the Role of Physical Therapy

Study Design. Retrospective cohort study. Objective. To evaluate the relationship between early physical therapy (PT) for acute low back pain and subsequent use of lumbosacral injections, lumbar surgery, and frequent physician office visits for low back pain. Summary of Background Data. Wide practice variations exist in the treatment of acute low back pain. PT has been advocated as an effective treatment in this setting although disagreement exists regarding its purported benefits. Methods. A national 20% sample of the Centers for Medicare and Medicaid Services physician outpatient billing claims was analyzed. Patients were selected who received treatment for low back pain between 2003 and 2004 (n = 439,195). To exclude chronic low back conditions, patients were excluded if they had a prior visit for back pain, lumbosacral injection, or lumbar surgery within the previous year. Main outcome measures were rates of lumbar surgery, lumbosacral injections, and frequent physician office visits for low back pain during the following year. Results. Based on logistic regression analysis, the adjusted odds ratio for undergoing surgery in the group of enrollees that received PT in the acute phase (<4 weeks) compared to those receiving PT in the chronic phase (>3 months) was 0.38 (95% confidence interval [CI], 0.360.41), adjusting for age, sex, diagnosis, treating physician specialty, and comorbidity. The adjusted odds ratio for receiving a lumbosacral injection in the group receiving PT in the acute phase was 0.46 (95% CI, 0.44–0.49), and the adjusted odds ratio for frequent physician office usage in the group receiving PT in the acute phase was 0.47 (95% CI, 0.44–0.50). Conclusion. There was a lower risk of subsequent medical service usage among patients who received PT early after an episode of acute low back pain relative to those who received PT at later times. Medical specialty variations exist regarding early use of PT, with potential underutilization among generalist specialties.

Osteoarthritis in the Disabled Population: A Mechanical Perspective

Primary disabling conditions, such as amputation, not only limit mobility, but also predispose individuals to secondary musculoskeletal impairments, such as osteoarthritis (OA) of the intact limb joints, that can result in additive disability. Altered gait biomechanics that cause increased loading of the intact limb have been suggested as a cause of the increased prevalence of intact limb knee and hip osteoarthritis in this population. Optimizing socket fit and prosthetic alignment, as well as developing and prescribing prosthetic feet with improved push‐off characteristics, can lead to reduced asymmetric loading of the intact limb and therefore are potential strategies to prevent and treat osteoarthritis in the amputee population. Research on disabled populations associated with altered biomechanics offers an opportunity to focus on the mechanical risk factors associated with this condition. Continued research into the causes of secondary disability and the development of preventive strategies are critical to enable optimal rehabilitation practices to maximize function and quality of life in patients with disabilities.

Quantitative neuromuscular ultrasound in intensive care unit–acquired weakness: A systematic review

Intensive care unit–acquired weakness (ICU‐AW) causes significant morbidity and impairment in critically ill patients. Recent advances in neuromuscular ultrasound (NMUS) allow evaluation of neuromuscular pathology early in critical illness. Here we review application of ultrasound in ICU‐AW. MEDLINE‐indexed articles were searched for terms relevant to ultrasound and critical illness. Two reviewers evaluated the resulting abstracts (n = 218) and completed full‐text review (n = 13). Twelve studies and 1 case report were included. Ten studies evaluated muscle thickness or cross‐sectional area (CSA): 8 reported a decrease, and 2 reported no change. Two studies reported preservation of muscle thickness in response to neuromuscular electrical stimulation, and 1 found no preservation. One study found decreases in gray‐scale standard deviation, but no change in echogenicity. One study described increases in echogenicity and fasciculations. Ultrasound reliability in ICU‐AW is not fully established. Further investigation is needed to identify ultrasound measures that reliably predict clinical, electrodiagnostic, and pathologic findings of ICU‐AW. Muscle Nerve 52: 701–708, 2015

Do Muscle Characteristics on Lumbar Spine Magnetic Resonance Imaging or Computed Tomography Predict Future Low Back Pain, Physical Function, or Performance? A Systematic Review.

To determine whether lumbar muscle characteristics on magnetic resonance imaging (MRI) or computed tomography (CT) can inform clinicians as to the course of future low back pain (LBP), functional limitations, or physical performance, in adults with or without LBP.

Cervical Facet-Mediated Pain

The cervical zygapophyseal joints, or facet joints, have long been implicated as a source of neck pain. This article examines the epidemiology of pain arising from these joints and relevant anatomy and histology. An emphasis on clinical findings, examination, and imaging are presented, as well as a focus on whiplash-associated pain.

A NOVEL SONOGRAPHIC METHOD OF MEASURING PATELLAR TENDON LENGTH

Obtaining accurate and readily repeatable measurements is a prerequisite for using measures of soft tissue structures both clinically and in the research setting. Few studies have evaluated the interrater reliability of ultrasound measurements of tendons. The objective of this study was to determine the accuracy and reliability of a new method of sonographic measurement of patellar tendon length using direct dissection as the gold standard. Four cadaveric knees were sonographically evaluated by two independent investigators. Two custom designed straps with nylon strapping and stainless steel wire were used to firmly mark position on the leg and create an acoustic shadow on the ultrasound image. Anatomic landmarks were the distal patellar pole and the bony ridge on the anterior proximal tibia. After sonographic evaluation, the knee was dissected to expose the patellar tendon, which was measured using digital calipers. Intraclass correlation coefficients (ICC) were used to determine reliability of measurements between observers, where ICC >0.75 was considered good and >0.9 was considered excellent. Validity was measured using a Bland-Altman plot, which measures bias between measurement methods as well as variability of scatter. Three sonographic measurements were made by each investigator on each tendon. The length of each of the four tendons based on the mean values of sonographic measurements was 53.8 mm, 53.4 mm, 49.4 mm and 46.8 mm. The length based on visual inspection of the dissected tissue was 54.6 mm, 52.8 mm, 49.8 mm and 46.9 mm. The calculated ICC between raters was 0.96. On the Bland-Altman plot, the bias, or mean difference between sonographic and visual measures, was 0.17 mm, with a standard deviation of 0.71. The 95% limit of agreement was -1.55 to 1.22 mm. Measurement of patellar tendon length with ultrasound using adjustable surface markers and calipers is highly accurate and has good interrater reliability.

Sonographic Evaluation of Trigger Finger at the Wrist and Carpal Tunnel Syndrome Resulting From a Deep Soft Tissue Leiomyoma

Trigger finger at the wrist is a unique condition in which finger motion results in triggering at the wrist. Suematsu et al1 classified this condition into 3 types: type A is caused by a tumor on the flexor tendon or flexor tendon sheath; type B is from an anomalous muscle belly; and type C is from a combination of a tumor and an anomalous muscle belly. The etiology is typically identified with imaging and confirmed on surgical exploration. We present a case of a deep soft tissue leiyomyoma triggering at the distal margin of the flexor retinaculum, causing both triggering of the fingers at the wrist and carpal tunnel syndrome. A 30-year-old right-hand–dominant woman presented with a 3-month history of atraumatic right volar wrist pain, “clicking” at the wrist with finger flexion, intermittent shooting pain and numbness into her fingers, and mild grip weakness. She otherwise denied persistent sensory loss or paresthesias. Physical examination of the right wrist and hand were only remarkable for a palpable click over the volar wrist with active finger flexion and extension and a positive Tinel sign. There were no palpable masses. Her range of motion, strength, and sensation were normal. Radiographs of the right wrist did not reveal any abnormalities. Sonography of the right wrist revealed a well-defined, noncompressible, heterogeneous, relatively hypoechoic mass measuring 18 mm in diameter (long axis) at the level of the carpal tunnel and in the vicinity of the second and third flexor tendons (Figure 1, A and B). The mass did not show any increased signal on power Doppler imaging. On dynamic evaluation, flexion and extension of the fingers caused the mass to abruptly translate in and out of the carpal tunnel (Videos 1 and 2). The median nerve measured at the pisiform was mildly enlarged, with a crosssectional area of 12 mm2. A cross-sectional area of greater than 10.5 to 11 mm2 at the level of the pisiform bone has been considered indicative of carpal tunnel syndrome.2,3 Magnetic resonance imaging (MRI) of the right wrist with contrast was obtained for further characterization and surgical planning. It revealed a 13 × 6 × 16-mm hyperintense T1 and mildly hyperintense T2 lesion with diffuse enhancement just distal to the carpal tunnel (Figure 1C). The lesion appeared to be localized between the flexor tendons and base of the third metacarpal. The patient was subsequently scheduled for an open excision of the soft tissue mass and carpal tunnel release. Surgical exploration through a longitudinal incision over the volar aspect of the wrist with complete release of the transverse carpal ligament revealed a 2 × 1-cm wellencapsulated, gray-white soft tissue mass that was adherent to the finger flexors (Figure 1D). Substantial inflammation of the tenosynovium was also noted within the carpal tunnel, prompting tenosynovectomy of the finger flexors. The mass was sharply excised without difficulty and sent for pathologic analysis. Histologic examination of the mass revealed spindle cells, and immunohistochemical analysis yielded positive results for α-smooth muscle actin and showed absence of nuclear β-catenin and S100 protein. These findings were most consistent with a leiomyoma. The patient followed up 12 days postoperatively and reported complete resolution of clicking, pain, and finger paresthesias. There have been 2 prior case reports that presented leiomyomas at the wrist, one resulting in triggering of the middle finger at the wrist4 and the other resulting in carpal tunnel syndrome.5 Our case is unique in that this individual had both triggering of the finger at the wrist and carpal tunnel syndrome. Furthermore, we were able to correlate sonographic characteristics with MRI and surgical pathologic findings. Sonographic characterization of soft tissue masses typically includes assessment of the size, depth, margins, echogenicity, consistency, vascularity, and relationship with surrounding structures. These features help differentiate between simple cystic, complex cystic, and solid lesions. Characteristic features of cystic lesions include sharp margins, internal hypoechogenicity or anecho genicity with a homogeneous echo texture, the presence of posterior acoustic enhancement, and the absence of intralesional vascularity.6 However, it is not uncommon for solid lesions to be mistaken as cystic. Lee et al6 reviewed 23 soft tissue masses incorrectly interpreted by sonography to be cystic lesions. It was noted that small masses (1–2 cm in diameter) tended to appear avascular on color Doppler imaging and were more likely to be mistaken as cystic. Additionally, although not uniformly observed, avascularity appeared to be evident on giant cell tumors of the tendon sheath, schwannomas, fibromas of the tendon sheath, gran-

Poster 352 Ultrasound-Guided Percutaneous Lavage of Calcific Rectus Femoris Tendinosis: A Case Report

Conclusion: The PEAK Platelet Rich Plasma System produces a PRP product that reflects the manufacturer’s specifications in terms of platelet, RBC and WBC concentrations; however, the final product contained a large number of RBCs and WBCs. It should be noted that the final PRP product contained as many RBCs as platelets in a ratio of 1.18 RBCs: 1 platelet. While the study confirms the manufacturer’s data, and thereby the reliability of the device, further research is required to verify the concentrations of the various cell types. Literature suggests that PRP with significant concentrations of RBCs could be detrimental when injected, especially within any joint space. These findings are of particular interest to physicians using this device to help treat their patients.

Quantitative neuromuscular ultrasound in intensive care unit-acquired weakness

Intensive care unit–acquired weakness (ICU‐AW) causes significant morbidity and impairment in critically ill patients. Recent advances in neuromuscular ultrasound (NMUS) allow evaluation of neuromuscular pathology early in critical illness. Here we review application of ultrasound in ICU‐AW. MEDLINE‐indexed articles were searched for terms relevant to ultrasound and critical illness. Two reviewers evaluated the resulting abstracts (n = 218) and completed full‐text review (n = 13). Twelve studies and 1 case report were included. Ten studies evaluated muscle thickness or cross‐sectional area (CSA): 8 reported a decrease, and 2 reported no change. Two studies reported preservation of muscle thickness in response to neuromuscular electrical stimulation, and 1 found no preservation. One study found decreases in gray‐scale standard deviation, but no change in echogenicity. One study described increases in echogenicity and fasciculations. Ultrasound reliability in ICU‐AW is not fully established. Further investigation is needed to identify ultrasound measures that reliably predict clinical, electrodiagnostic, and pathologic findings of ICU‐AW. Muscle Nerve 52: 701–708, 2015