Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies

Axonal degeneration, indicative of surgical decompression, may coexist in carpal tunnel syndrome (CTS) as the disease progresses. However, the current ...

The University of Hong Kong

Fractures of the proximal phalanges of the hands can be treated by many methods. With surgical intervention, a loss in proximal interphalangeal joint movement is common. Using the stabilizing effect of the zancolli complex-metacarpophalangeal retention apparatus and an external device such as a thermoplastic metacarpophalangeal block splint, proximal phalangeal fractures can be stabilized in terms of axis, length, and rotation.This study reports the authors' 10-year results managing these fractures with dynamic treatment. All patients with closed fractures of the proximal phalanges admitted to Queen Mary Hospital, Hong Kong, China, between July 2000 and June 2010 were analyzed. Fractures with rotational deformities or displaced intra-articular configurations were excluded. A dynamic splint that kept the metacarpophalangeal joint maximally flexed while allowing free movement of the proximal and distal interphalangeal joints of the injured finger was applied for at least 4 weeks. Results were evaluated using the Belsky classification and grip strength assessment. The results of 97 patients (103 fractures) were analyzed. At a minimum 1-year follow-up, 75% of patients attained excellent or good results. Neither nonunion nor delayed fracture union was noted. The 25% of patients who attained poor results were older than those who attained excellent or good results (average age, 53.1 vs 35.1 years, respectively) and tended to comply poorly with the rehabilitation program. Using the stabilizing effect of the zancolli complex-metacarpophalangeal retention apparatus and a metacarpophalangeal block splint, bone healing and movement recovery can be achieved simultaneously.

Ten-year results using a dynamic treatment for proximal phalangeal fractures of the hands.

Degradable bone graft substitute for large-volume bone defects is a continuously developing field in orthopedics. With the advance in biomaterial in past decades, a wide range of new materials has been investigated for their potential in this application. When compared to common biopolymers within the field such as PLA or PCL, elastomers such as polyurethane offer some unique advantages in terms of flexibility. In cases of bone defect treatments, a flexible soft filler can help to establish an intimate contact with surrounding bones to provide a stable bone-material interface for cell proliferation and ingrowth of tissue. In this study, a porous filler based on segmented polyurethane incorporated with poly l-lactic acid was synthesized by a phase inverse salt leaching method. The filler was put through in vitro and in vivo tests to evaluate its potential in acting as a bone graft substitute for critical-sized bone defects. In vitro results indicated there was a major improvement in biological response, including cell attachment, proliferation and alkaline phosphatase expression for osteoblast-like cells when seeded on the composite material compared to unmodified polyurethane. In vivo evaluation on a critical-sized defect model of New Zealand White (NZW) rabbit indicated there was bone ingrowth along the defect area with the introduction of the new filler. A tight interface formed between bone and filler, with osteogenic cells proliferating on the surface. The result suggested polyurethane/poly l-lactic acid composite is a material with the potential to act as a bone graft substitute for orthopedics application.

Biological Evaluation of Flexible Polyurethane/Poly l-Lactic Acid Composite Scaffold as a Potential Filler for Bone Regeneration.

Carpal tunnel syndrome (CTS) accompanied by secondary axonal degeneration cannot be clearly discriminated using the current cross-validated ultrasound severity classification system. This study aimed at exploring cut-off values of ultrasound parameters, including wrist cross-sectional area (W-CSA), wrist perimeter (W-P), ratio of cross-sectional area (R-CSA) and perimeter (R-P), changes of CSA and P from wrist to one third distal forearm (ΔCSA&ΔP) for differentiation. Seventy-three patients (13 male and 60 female) were assigned into group A (demyelination only, n = 40) and group B (demyelination with secondary axonal degeneration, n = 33) based on the outcomes of nerve conduction studies (NCS). Receiver Operative Characteristics (ROC) curves were plotted to obtain sensitivity, specificity, and accuracy of cut-off values for all the ultrasound parameters. The overall identified cut-off values (W-CSA 12.0 mm, W-P 16.27 mm, R-CSA 1.85, R-P 1.48, ΔCSA 6.98 mm, ΔP 5.77 mm) had good sensitivity (77.1-88.6%), fair specificity (40-62.2%) and fair-to-good accuracy (0.676-0.758). There were also significant differences in demographics (age and severity gradation, P < 0.001), NCS findings (wrist motor latency and conduction velocity, P < 0.0001; wrist motor amplitude, P < 0.05; distal sensory latency, P < 0.05; sensory amplitude, P < 0.001) and ultrasound measurements (W-CSA, W-P, R-CSA, R-P, ΔCSA&ΔP, P < 0.05) between groups. These findings suggest that ultrasound can be potentially used to differentiate demyelinating CTS with secondary axonal degeneration and provide better treatment guidance.

Wing-Yuk Ip

Department of Orthopedics & Traumatology

The University of Hong Kong

Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies

Wing-Yuk Ip

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Orthopedics & Traumatology

The University of Hong Kong

Screening of Axonal Degeneration in Carpal Tunnel Syndrome Using Ultrasonography and Nerve Conduction Studies

Department of Orthopedics & Traumatology