Risk of neurovascular injury with limited-open carpal tunnel release: defining the "safe-zone".

Limited-open carpal tunnel release was performed in ten cadaver arms using the "Safeguard" system. The "Safeguard" guide was intentionally placed off of the longitudinal middle/ring finger axis, either in 15 degrees of radial deviation or 15 degrees of ulnar deviation. Despite the errant placement, carpal tunnel release was performed without damage to any neurovascular structure. The proximity of neurovascular structures to the middle/ring finger axis was measured in all ten cadaver specimens. From this, a "safe-zone" was defined for endoscopic or limited-open carpal tunnel release. The "safe-zone" expands when surgery is performed from distal to proximal. The area of the "safe-zone" is greatest when a protective guide is placed between the bursal sac of the carpal canal and the flexor retinaculum.

The treatment of trapeziometacarpal arthritis with arthrodesis.

In this article, the authors discussed the indications for TM arthrodesis, the surgical approach, the types of fixation, expected outcome, and complications. Fusion of the thumb TM joint allows maintenance of pinch and grip strength and provides relief of pain, but limits thumb mobility. An important factor in the success of the arthrodesis is correct thumb position. Trapeziometacarpal joint arthrodesis is advantageous over soft tissue interposition when grip and pinch strength are to be maintained. After TM fusion, however, there are increased stresses across the peritrapezial joints that can cause laxity, pain, and arthritis. Treatment of this may require additional surgical intervention. Treatment of TM arthritis with soft tissue interposition has the advantages of pain relief and increased mobility, but pinch and grip strength are reduced to approximately 75% of normal and rate of reoperation is minimal. The authors recommend TM arthrodesis in the young active person with arthritis limited to the TM joint in whom strong pinch and grip are required. Arthrodesis of the TM joint is safe and predictable and has good subjective and objective results.

Benefits of radioimmunoguided surgery for pelvic recurrence.

AIM: Surgery for recurrent rectal cancer is usually traumatic and of questionable curative value. The use of radioimmunoguided surgery (RIGS) in enhancing the surgeon's assessment of the extent of disease in these patients was investigated. METHODS: Twenty-one patients diagnosed with recurrent pelvic cancer were operated using the RIGS(O)system. Preoperative assessment included CTs of chest, abdomen and pelvis as well as colonoscopy. Patients were injected with CC49, a monoclonal antibody (MoAb) labelled with 125I. Surgical exploration was followed by survey with the gamma-detecting probe. RESULTS: Surgical exploration identified eight intra-colorectal recurrences, nine extra-colonic pelvic recurrences and five extra-pelvic lymph node metastases. RIGS exploration confirmed all intra-colonic recurrences except for one (patient with no MoAb localization), identified 13 pelvic recurrences and 10 lymph node metastases. There were seven patients with occult findings (33%), resulting in a modified surgical procedure. Surgery included five abdomino-perineal resections, six low anterior resections, seven excisions of presacral tumour, eight total abdominal hysterectomy and bilateral salpingo-oophorectomy, one pelvic exenteration and one post-exenteration. There were no operative deaths. Eight patients had minor complications, and one patient had a major complication with reoperation due to urinary leak. The mean follow-up was 18 months. Ten patients died of disease. CONCLUSION: Although not curative, RIGS can help the surgeon in the decision-making process through better disease staging.

Immunoguided lymph node dissection in colorectal cancer: a new challenge?

Knowledge of lymphatic involvement in patients with colorectal cancer is important in surgery and in the postoperative decision-making process. Fifty-eight patients with recurrent colorectal cancer underwent operation with the RIGS/(Radioimmunoguided Surgery) technology. Preoperatively, patients were injected with 1 mg monoclonal antibody (MoAb) CC49 (anti-TAG-72-tumor-associated glycoprotein) labeled with 2 mCi of iodine 125. Traditional surgical exploration was followed by survey with a gamma-detecting probe. Localization of MoAb on tumor was noted in 54/58 patients (93%). Traditional exploration identified 117 suspected tumor sites. With RIGS, 177 suspected tumor sites were detected. In 17 of the 58 patients (27.5%), at least one occult tumor site identified by RIGS was confirmed by pathology with hematoxylin & eosin (H & E) staining. This finding resulted in 16 major changes in surgical plan. RIGS performance varied between lymphatic and non-lymphatic tissue, with a positive predictive value (PPV) of 95.6% and negative predictive value (NPV) of 90% in non-lymphoid tissue compared to PPV of 40% and NPV of 100% in lymphoid tissue. In patients with tumors that localize, no RIGS activity in lymph nodes signifies no tumor, while decisions based on RIGS activity in lymph nodes requires H & E confirmation. Using this guideline, additional information acquired by RIGS can help the surgeon in making an informed decision during surgery and in planning postoperative therapy.

Identification of lymph node metastases in recurrent colorectal cancer.

Lymph node metastases are an important prognostic prediction factor in patients with recurrent colorectal cancer, particularly those with liver metastasis. Fifty-six patients with recurrent colorectal cancer were operated by us using the RIGS (radioimmunoguided surgery) technology. Patients were injected with 1 mg monoclonal antibody (MoAb) CC49 labeled with 2 mCi 125I. In surgery, traditional exploration was followed by survey with a gamma-detecting probe. Sixty of 151 patients enrolled in the Neo2-14 Phase III study for recurrent colorectal cancer were diagnosed with liver metastases based on preoperative CT. In 17/56 patients (30%), RIGS identified at least one tumor site confirmed by pathology (H&E). This resulted in 16 major changes in surgical plan. RIGS performance varied between lymphatic and non-lymphatic tissue, with positive predictive value (PPV) of 100% and negative predictive value (NPV) of 94% for non-lymphoid tissue, compared to PPV of 46.5% and NPV of 100% for the lymphoid tissue. Thirty-five out of 60 patients were considered resectable after traditional evaluation. RIGS identified occult tumor in 10 of these patients (28.5%). 7/10 occult patients expired (70%), while only 7/25 of the non-occult patients expired (28%) (P = 0.046). In localizing patients, no RIGS activity in lymph nodes signifies no tumor, while H&E confirmation is needed for decisions based on RIGS activity in the lymph nodes. RIGS provides important staging information, identifying patients for whom surgery may be done with curative intent.

Traumatic dislocation of trapezium: case report and review of the literature.

A complete dislocation of the trapezium from its fossa is rare. We present a case of a 36-year-old man with a complete ulnar and volar dislocation of the trapezium. The trapezium was reduced with manual manipulation and was held in anatomic position by using multiple Kirschner wires. The patient's clinical course is reviewed and similar cases from the literature are discussed.

A comparison of plate and pin fixation for arthrodesis of the rheumatoid wrist.

This retrospective study compared plate fixation versus pin fixation in 57 patients with rheumatoid arthritis who underwent wrist arthrodesis. Fixation was achieved by using plates in 32 patients and longitudinal pins in 25 patients. Clinical follow-up averaged 29 months (range: 12-57 months) and radiographic follow-up averaged 16 months (range 12-39 months). Union occurred in 97% of the wrists fixed with plates and in 96% of the wrists fixed with pins. There were 6 (19%) complications in the plate group and 7 (28%) complications in the pin group. Three (12%) wrists fixed with pins moved from the immediate postoperative position to a position of relative volar flexion, while radiographs showed no changes in wrist position in the plate group. With both methods, successful arthrodesis stabilized the wrist in a high percentage of patients. Plate fixation offers an excellent alternative method for arthrodesis of the rheumatoid wrist.

The role of arthroscopy in wrist arthritis.

Recent advances in arthroscopic surgery techniques and instrumentation have enabled the surgeon to improve the treatment of wrist pathology. The arthroscopist can now perform a proximal row carpectomy or radial styloidectomy with minimal dissection and potentially less morbidity. The surgery requires a high level of skill from the surgeon. This is an area of medicine that is still evolving. Long-term studies are lacking but short-term results are promising. In the near future, the role of arthroscopy will better be defined as more research becomes available.

The role of arthroplasty and arthrodesis following trauma to the upper extremity.

Intra-articular fractures in the hand and wrist are common. Prompt treatment with adequate fixation to allow early motion provides the best chance for a successful outcome. Arthrodesis and arthroplasty are the two main options for treatment of residual pain, deformity, or instability in the hand. Management of late wrist symptoms may include proximal row carpectomy, limited wrist fusion, or complete wrist fusion.

Fractures of the elbow.

Elbow fractures encompass a spectrum of severity from low energy nondisplaced fractures to high energy fractures with associated severe soft-tissue injury. Treatment is based on fracture pattern, patient age, bone quality, associated soft-tissue injuries, and associated fractures. The basis for treatment relies on the knowledge of the complex osseous and soft-tissue anatomy of the elbow. The goals of operative and nonoperative treatment are to achieve a stable, anatomic reduction that allows early motion to maximize function.

Localization of monoclonal antibody CC49 in colonic metastasis from renal cell carcinoma.

We report a rare case of solitary metastasis from renal cell carcinoma which manifested as a primary colonic tumour 5 years after nephrectomy. A monoclonal antibody CC49 (anti-TAG-72 antibody), used in Radioimmunoguided Surgery, was found to localize in the tumour. Pathological examination revealed metastasis of renal cell carcinoma in the colon. Immunohistochemistry with CC49 showed moderate staining of the colonic mucosa around the metastasis with no reaction in the tumour itself. Based on this case and other published studies, we conclude that TAG-72, the antigen manifested in many adenocarcinomas, can be up-regulated and expressed in normal colonic mucosa adjacent to another tumour as a result of stimulations, such as cytokine release, in response to this tumour.

Shared tumor antigens in colorectal carcinoma and neuroendocrine tumors.

ND4 monoclonal antibody recognizes a tumor marker found on poorly differentiated colorectal cancer. We demonstrate its expression in 25% of gastrointestinal neuroendocrine tumors, which also express CEA in 37% of cases. As in colorectal cancer the ND4 marker is predominantly membrane bound in a colonic neuroendocrine tumor cell line, LCC-18 (p < 0.05). The ND4 marker is absent in a poorly differentiated colorectal cancer cell line that does not express CEA or other tumor antigens. Shed antigen in the serum of patients with neuroendocrine tumors is detected in only five of seven patients with the carcinoid syndrome and two of four of those without evidence of the syndrome. However, the reactivity was less in the patients with localized disease, and this test is unlikely to be of diagnostic utility in this group of patients. The sharing of this antigen in colorectal cancer and neuroendocrine tumors is not universal, but does support the common-cell progenitor theory for the origin of these tumors.

Fixation of phalangeal fractures.

The indications and methods for operative treatment of phalangeal fractures are reviewed. Included are descriptions with examples of closed reduction and percutaneous pin fixation, percutaneous reduction and percutaneous fixation, open reduction and internal fixation, and static and dynamic external fixation. Also included are tips for facilitating phalangeal fixation and a description of potential complications.

Radioimmunoguided surgery benefits for recurrent colorectal cancer.

BACKGROUND: Despite new adjuvant therapy, 50% of patients with colon cancer will have recurrent disease. This study investigated the use of a radiolabeled monoclonal antibody in locating occult tumor during surgery for recurrent colorectal cancer. METHODS: Twenty-two patients with recurrent colorectal cancer underwent surgery using the radioimmunoguided surgery (RIGS) system. All patients were subjected to abdominal and chest computed tomography (CT). Before surgery, patients were injected with the CC49 monoclonal antibody (MoAb), anti-TAG antibody labeled with 125I. Ten patients with elevated carcinoembryonic antigen (CEA) levels and no CT findings had a scintigraphy scan with an anti-CEA MoAb labeled with 99Tc. Human antimouse antibody levels of these patients were within normal limits. Surgical exploration including liver ultrasound examination was followed by survey with a gamma-detecting probe (GDP). RESULTS: There was MoAb tumor localization in 100% of the patients. CT found nine tumor sites, traditional surgical exploration 30, and the GDP 51, with 44 confirmed by pathology (hematoxylin and eosin). The RIGS system found occult tumor in 10 patients (45.4%) and resulted in major changes in surgical procedure in 11 patients. In the 10 patients who had scintigraphy scans, 10 tumor sites were identified, whereas RIGS found an additional eight sites. CONCLUSION: RIGS technology offers a substantial benefit for patients undergoing surgery for recurrent colorectal cancer and a better chance of finding recurrent tumor intraoperatively in patients who have elevated CEA levels with no other CT findings.

Correlation of wrist ligamentotaxis with carpal distraction: implications for external fixation.

Cadaver forearms were tested to measure carpal bone separation and wrist ligament tension in response to MTS-based incremental wrist distraction. Distraction of 2 mm separated the proximal carpal row from the radius and transmitted an average tension of 8 N. The mid-carpal joint also began to widen at this level of distraction. Distraction of 4 mm resulted in an average tension of 20 N. At this level of distraction, radioscaphoid separation started to exceed radiolunate separation. A transition from low- to high-stiffness response was observed over a range of 4-8 mm distraction for the 12 specimens tested, with an average tension of 80 N associated with 8 mm distraction. Average values of carpal height ratio, revised carpal height ratio, and carpal height index were found to be poor indicators of distraction, owing to their high variability between specimens.

Displaced intra-articular fractures of the distal radius: the effect of fracture displacement on contact stresses in a cadaver model.

Contact stresses in the wrist were measured after simulating displaced fractures of the lunate fossa in the distal radius of eight human cadaver arms. Osteotomies created displaced lunate fossa fractures of 0, 1, 2, and 3 mm. Contact stresses were measured with Fuji pressure-sensitive film after loads of 100 N were applied to the wrist through wrist flexor and extensor tendons. Mean contact stresses were significantly increased with step-offs of 1 mm or more. Maximum stresses and overloaded areas were significantly increased with step-offs of 2 mm or more. As the magnitude of the fracture displacement increased, there was a shift in the focus of the maximum stresses toward the fracture line. In this model, simulated displaced die-punch fractures created alterations in both the magnitude and location of contact stresses in the wrist joint.

Elevated serum iron predicts poor response to interferon treatment in patients with chronic HCV infection.

To date, there are no firm clinical, demographic, biochemical, serologic, or histologic features predicting which patients with chronic hepatitis C are more likely to respond to therapy with interferon-alpha. Serum iron, total iron-binding capacity, transferrin saturation, and ferritin were measured in the fasting state. The amount of stainable iron in liver biopsy specimens was evaluated histochemically as well. All patients received subcutaneous recombinant human IFN-alpha 2a three million units thrice weekly by self-administration. Eleven of 13 (84%) responders had low to normal serum iron levels as compared to one of 26 (4%) nonresponders (P < 0.001). The serum transferrin was similar in both groups, but iron saturation was significantly lower in responders (30 +/- 10%) than in nonresponders (53 +/- 12%) (P< 0.001). Serum ferritin and hepatic iron content were higher in nonresponders (NS). It is suggested that increased serum iron and transferrin saturation blunt the action of interferon, as they have opposite effects on the immune system. Iron overload can thus lead to a poor response to interferon. It remains to be seen whether reducing iron overload will improve the response to interferon therapy.