A prospective evaluation of untreated acute grade III acromioclavicular separations.

We prospectively studied the natural history of untreated acute grade III acromioclavicular separations. Twenty-five patients were treated nonoperatively with a sling for comfort through progressive early range of motion as tolerated. Ten additional uninjured subjects underwent strength testing to evaluate the difference between the dominant and nondominant sides so that patient data could be standardized. The patients were examined at intervals of 6, 12, 24, 36, and 52 weeks after injury, at which time they completed a subjective questionnaire and underwent isometric dynamometer testing as well as military press and bench press strength testing. One patient underwent a surgical procedure at 2 weeks after injury because of cosmetic concerns. Twenty of the 25 patients completed the 1-year evaluation and strength-testing protocol. Subjectively, 4 of the 20 patients (20%) thought that their long-term outcome was suboptimal, although for 3 of them it was not enough to warrant surgery. Objective examination and strength testing of the 20 patients revealed no limitation of shoulder motion in the injured extremity and no difference between sides in rotational shoulder muscle strength. The bench press was the only strength test that showed a significant short-term difference, with the injured extremity being an average of 17% weaker. This study documents the natural history of patients with an untreated acute grade III acromioclavicular separation and provides a reference with which to judge all other proposed methods of treatment.

Axillary nerve temperatures during radiofrequency capsulorrhaphy of the shoulder.

PURPOSE: The purpose of this study was to determine the temperatures along the course of the axillary nerve during radiofrequency (RF) capsulorrhaphy of the shoulder in a cadaver model. The hypothesis of this project was that temperatures capable of damaging neural tissue would be recorded during simulated RF capsulorrhaphy. TYPE OF STUDY: Basic science evaluation. METHODS: This study used 9 fresh-frozen cadaver shoulder capsules removed en bloc along with the underlying axillary nerve and soft tissue. The axillary nerve was instrumented with 4 thermocouples placed along the course of the nerve (2 thermocouples anterior and 2 posterior to the 6 o'clock position, spaced 7 mm apart). Each of the specimens underwent RF thermal capsulorrhaphy during which the temperature at each of the thermocouple positions was continuously recorded. RESULTS: The average of the maximum temperature at each of the 4 positions measured along the course of the axillary nerve were 52.2 +/- 18.0 degrees C at the most anterior place probed, 45.8 +/- 5.44 degrees C (mid anterior), 44.5 +/- 8.7 degrees C (mid posterior), and 42.8 +/- 10.1 degrees C at the most posteriorly positioned probe. Two specimens had a maximum temperature greater than the 67 degrees C set point of the device, and 7 specimens had a maximum temperature greater than 45 degrees C in at least 1 thermocouple position. CONCLUSIONS: This study shows that heating of the axillary nerve can occur during RF capsular shrinkage of the shoulder and may potentially reach levels that can damage neural tissue.

Obtaining intra-articular bone grafts arthroscopically for intra-articular grafting.

Autogenous bone graft is frequently necessary for arthroscopic procedures and even small open procedures that involve cruciate revision, osteochondritis dissecans repair, and fracture reduction and internal fixation. Currently used sites to obtain bone graft are the iliac crest and Gerdy's tubercle. This article describes an arthroscopic technique for harvest of small amounts of bone graft from the distal femur. This avoids the morbidity of the extra-articular harvest. Tube harvesters frequently used for osteochondral autografts are the primary tool required for this technique. However, as described, the obtaining of bone graft is much less technically exacting than when procuring osteochondral bone plugs. This provides a safe, simple way to obtain extra autogenous bone at minimal additional operative morbidity.

The influence of tendon length and fit on the strength of a tendon-bone tunnel complex. A biomechanical and histologic study in the dog.

Using a dog model, we examined the influence of tendon length and fit within a bone tunnel on the pull-out strength of a tendon-bone tunnel complex at 6 weeks after fixation. Fourteen adult mongrel dogs (weight, 25 to 30 kg) underwent bilateral hindlimb surgery in which the extensor digitorum longus tendon was transplanted into an extraarticular metaphyseal bone tunnel. Our findings demonstrated that pull-out strength at 6 weeks was enhanced by increasing the length of tendon within the tunnel. The average load to failure with 1 cm of tendon within the tunnel was 153.7 +/- 78.6 N, compared with 265.5 +/- 93.3 N for the specimens with 2 cm of tendon in the tunnel. Tendon fit within the tunnel was also found to be important. The average load to failure when a tendon was placed in a 4.2-mm diameter tunnel was 301 +/- 61 N at 6 weeks. The average load to failure when the tendon was placed within a 6-mm diameter tunnel was 228 +/- 65 N. These differences were statistically different. Histologically, the interface between the tendon and bone appeared to be most mature when there was intimate bone-to-tendon contact. These data suggest that maximizing tendon length within a bone tunnel and minimizing tendon-tunnel diameter mismatch will maximize the strength of a tendon-bone tunnel complex at 6 weeks.

Axillary nerve injury after thermal capsular shrinkage of the shoulder.

The purpose of this study was to evaluate 4 cases in which axillary nerve injury was observed after radiofrequency capsular shrinkage of the shoulder. These cases were used to evaluate the clinical circumstances under which axillary nerve injury occurred, the time frame over which these injuries recovered, and the ultimate outcome observed in these patients. The case histories of each of these 4 patients were carefully evaluated. In 2 of the 4 cases, purely sensory findings were found, and in 2 cases both sensory and motor injuries occurred. In each case the inferior axillary recess was treated using the Oratech Interventions Tac-S probe. The authors conclude that injury to the axillary nerve during this procedure is possible and postulate that heat penetration through the capsule to the nerve is the most likely cause of injury.

Pitfalls associated with fixation of osteochondritis dissecans fragments using bioabsorbable screws.

The purpose of this study was to evaluate 2 cases in which bioabsorbable screw fixation for an osteochondritis dissecans lesion of the femoral condyle resulted in complications necessitating the need for secondary surgery. We reviewed the case history of these patients and described the circumstances under which the bioabsorbable screws were used, the events leading to the need for secondary surgery, and the ultimate outcome. In the 2 cases presented, these implants were found to retain their mechanical stiffness for many months. This resulted in articular damage in 1 case after the treated lesion failed to heal. In the second case, screw breakage 8 months after implantation resulted in it becoming a loose body, which required removal during a second arthroscopic procedure. We conclude that these implants retain their mechanical properties for many months and cannot be relied on to degrade quickly. If a treated lesion fails to heal, these implants can cause mechanical problems due to their retained structural properties.

Pathology residents' use of a Web-based tutorial to improve Gleason grading of prostate carcinoma on needle biopsies.

Little is known about pathology residents' ability to Gleason grade or their ability to learn surgical pathology using Internet-based technology. A free Web-based program (available at www.pathology. jhu.edu/prostate) was developed that consisted of 20 pretutorial images for grading, 24 tutorial images, and the same 20 posttutorial images for Gleason grading. The grading images were selected from cases that had a consensus Gleason grade from 10 uropathology experts. In 2.5 months, 255 residents visited the website, and 151 (59%) completed it. Of those who completed the website, their year in training was known in 85 (56%): 1st year, 25.8%; 2nd year, 20%; 3rd year, 22.3%; 4th year, 14.1%; 5th year, 15.3%; and 6th year, 2.4%. Eighty percent learned Gleason grading in residency versus being self-taught, and 66% were male. In a multivariate analysis, higher pretutorial scores were associated with both their year in training (P = .001) and their hospital size (P = .003). Improvements in grading posttutorial were not related to the residents' year in training. Overall, the website significantly improved grading in 11 of 20 images and had no effect in 9 of 20 images. Improvements were noted in 1 of 1 Gleason score 4; 2 of 7 Gleason score 5 to 6; 2 of 6 Gleason score 7; and 6 of 6 Gleason score above 7 tumors. In summary, a Web-based tutorial improved Gleason grading accuracy by pathology residents to an equal extent regardless of their year in training. It is more difficult to teach residents to grade Gleason scores 5 to 7 tumors, and additional training should be concentrated in this area.

The effect of reconstruction of the medial patellofemoral ligament on patellar tracking.

We evaluated patellar tracking in six cadaveric knees with the medial restraints intact and then sectioned to determine their contribution to lateral translation of the patella with and without a lateral force on the patella. The medial patellofemoral ligament was then reconstructed with a gracilis tendon graft and patellar tracking was again evaluated. The knees were extended using a materials testing machine, and patellar tracking was measured with a position sensing system. With no lateral force applied to the patella, patellar tracking was unaffected by the presence or absence of the medial restraints or by reconstruction of the medial patellofemoral ligament. With a lateral force applied to the patella, patellar tracking was changed significantly by the loss of the medial restraints. Normal patellar tracking was substantially restored by reconstruction of the medial patellofemoral ligament.

Histopathologic features of ovaries at increased risk for carcinoma. A case-control analysis.

In this study, the pathogenesis of ovarian carcinoma was investigated by performing a masked histopathologic comparison of benign ovaries removed from 61 women predicted to be at increased risk for developing carcinoma (cases) with ovaries removed from 121 women without known predisposing conditions (controls). The cases included 26 women who had a unilateral invasive carcinoma and 35 women undergoing prophylactic oophorectomy for a family history of ovarian cancer. As predicted by previously developed models, epithelial inclusion cysts were identified more frequently with advancing age in both cases and controls. However, the mean and maximum number of cysts per slide in a woman were not increased among cases. Surface epithelial "atypia," a designation based on a composite impression of multiple features, was found in 13% of cases compared with 3% of controls (relative risk 7.1; 95% confidence interval, 1.9 to 26.1), but this result was based on small numbers. None of the other histologic features examined was found more often in cases following age-adjustment. Reexamination of sections with well-preserved surface epithelium or inclusion cysts under oil immersion demonstrated several differences in the detection of specific features between cases and controls and increased detection of "atypia" among cases, but none of these findings reached statistical significance. It is concluded that there may be subtle differences in the surface epithelium of ovaries predisposed to developing cancer as compared with controls, but these changes are difficult to identify reliably with light microscopy. Future etiologic studies should attempt to optimize specific handling and include molecular studies and epidemiologic analyses.

Comparison of humeral head retroversion with the humeral axis/biceps groove relationship: a study in live subjects and cadavers.

The purpose of this study was to investigate whether the axis of the humeral articular surface bears a more constant relationship to the bicipital groove than to the distal humerus. This finding could help intraoperative placement of a shoulder prosthesis in the most anatomic position. Magnetic resonance imaging was used in 41 live volunteers and 9 cadavers to measure the distance from the biceps groove to a line drawn perpendicular to the midpoint of the humeral articular surface. A cadaver model with a plastic humeral prosthesis was used to convert this biceps distance into an angular measurement. The relationship between the biceps distance and the retroversion angle of the humeral head with respect to the humeral epicondyles was analyzed. The biceps distance averaged 11.8 mm+/-3.5 mm (equivalent to 26.8 degrees+/-8.3 degrees), whereas retroversion averaged 26.8 degrees +/-12.2 degrees. This difference in variability is significant (P=.008). Placing the fin of a humeral head implant 12 mm posterior to the biceps groove reproduces normal anatomy better than the use of an arbitrary standard of 30 degrees to 40 degrees of retroversion.

Biomechanical evaluation of lateral patellar dislocations.

This investigation was undertaken to identify the structures torn within the medial retinaculum and localize the injury site anatomically following acute lateral dislocation of the patella in a cadaver model. The patellae of 10 fresh-frozen cadavers were translated laterally 135% of the patella width on a universal testing instrument. Magnetic resonance imaging (MRI) was performed on all specimens prior to testing and immediately following testing. Anatomical dissection also was performed on the medial retinaculum following testing. Dissection revealed avulsion fractures from the inferomedial border of the patella in 8 of the 10 knees. The medial patellofemoral ligament was injured in 8 of the 10 knees; the location of the injury varied. Tears of the medial patellofemoral ligament from the femur in 6, a midsubstance tear in 1, and stretch in 1 knee were noted. In a knee with a femoral-sided tear, an avulsion fracture of the medial patellofemoral ligament was identified. None of the cadaver knees demonstrated tears of the lateral retinaculum or medial patellotibial ligaments on dissection. Review of the MRIs revealed a medial retinaculum tear in 6 of the 10 knees. Two tears from the femur, 3 from the patella, and 1 tear from both the patella and femur were noted. An avulsion fracture was noted from the inferomedial patellar border in 3 of the 10 knees. No pathology was noted on 4 of the MRIs. When anatomically correlated, the 3 patellar retinacular tears and 3 avulsion fractures noted on MRI represented a tear of the medial patellomeniscal ligament from the patella. The femoral-sided tear represented a tear of the medial patellofemoral ligament from the femur. An appreciation of the spectrum of injury to the medial retinaculum may aid in the diagnosis of an acute dislocation of the patella and help establish the anatomical structures damaged. The pathology demonstrated in this study may explain the diversity of injury seen clinically. Whereas an avulsion fracture from the patella may represent the medial patellomeniscal ligament, a femoral-sided retinacular tear may represent the medial patellofemoral ligament. This may lead to future refinements of surgical options and anatomic restoration of the damaged structure.

Soft tissue restraints to lateral patellar translation in the human knee.

The purpose of this investigation was to identify and quantify the soft tissue restraints, both medially and laterally, to lateral patellar translation. These restraints to lateral patellar translation at 20 degrees of knee flexion were tested biomechanically on a universal testing instrument in nine fresh-frozen cadaveric knees. After preconditioning the tissues, the patella of each intact knee was translated laterally to a distance at which a force of 200 N was recorded. This distance was used to translate the patella for the remaining structures to be sectioned. The contribution of each structure to the total restraining force was determined as the percent of the force to restrain the intact specimen by sectioning the restraints in a predetermined order. The contribution of each structure to the restraining force was defined as the difference between the restraining force before and after its sectioning. The medial patellofemoral ligament was found to be the primary restraint to lateral patellar translation at 20 degrees of flexion, contributing 60% of the total restraining force. The medial patellomeniscal ligament contributed 13% of the total force, and the lateral retinaculum contributed 10%. The medial patellotibial ligament and superficial fibers of the medial retinaculum were not functionally important in preventing lateral translation. The previously unrecognized contribution of the lateral retinaculum as a restraint to lateral patellar translation may shed new light on the failures of isolated lateral release for acute lateral dislocation of the patella.

DCC genetic alterations and expression in endometrial carcinoma.

DCC (Deleted in Colorectal Carcinoma) is a candidate tumor suppressor gene located on the long arm of chromosome 18. DCC was initially identified and cloned during a search for the target gene located in a region of 18q that demonstrated loss of heterozygosity (LOH) in 70 to 80% of colorectal cancers. More recently, the region of 18q harboring the DCC gene has been shown to undergo LOH in approximately 14 to 30% of endometrial carcinomas. These findings suggest that DCC may be a target of LOH in at least some endometrial carcinomas and, therefore, may have a role in the pathogenesis of this common malignancy of the female genital tract. To address this possibility, we analyzed 26 cases of endometrioid endometrial carcinoma for DCC LOH and alterations in an AT microsatellite repeat located in an intron of the DCC gene. LOH was detected in one case (4%). Allelic shifts at the DCC AT repeat were detected in five (19%) additional cases. We also evaluated DCC protein expression by immunohistochemical analysis in normal, hyperplastic, and neoplastic endometrial tissues. Three proliferative and five secretory endometria and one simple endometrial hyperplasia demonstrated staining for DCC. Four of the 26 endometrioid endometrial carcinomas for which frozen tissue was available, including at least one from each histologic grade, and a case of endometrioid carcinoma confined to the endometrium completely lacked detectable staining for DCC. Although DCC LOH was infrequent in endometrial carcinomas, alterations of the gene (LOH or AT repeat alterations) were not uncommon (23% of our cases). In addition, DCC was expressed in normal endometrial tissue, whereas expression was lost in all of the five endometrial carcinomas. The combination of the genetic alterations and loss of DCC protein expression suggests that inactivation of the DCC gene may play a role in the pathogenesis of endometrial carcinoma.

Fifteen-year follow-up of arthroscopic partial meniscectomy.

From an original pool of 283 patients, 146 patients who had undergone arthroscopic partial meniscectomy an average of 14.7 years before were followed-up. Lysholm score, Tegner activity level, satisfaction index on a scale of 1 to 10, and standing anteroposterior and flexion weight-bearing radiographs of both knees, were obtained. A physical examination was performed on each knee emphasizing motion, swelling, and ligament evaluation. Radiographs were graded for degenerative changes for each knee. Each knee joint space was also measured in millimeters and compared, operative knee with unoperated knee. The unoperated knee had no injuries or surgeries and was used as a control. Patients were 83% male and 17% female; 78% had undergone medial meniscectomies, 19% lateral, and 3% both. There were 88% good and excellent results in anterior cruciate ligament-stable knees. The radiographic grade side-to-side difference showed the operative knee to be only a 0.23 grade worse than the nonoperative knee. Age at the time of meniscectomy was not found to be a factor. Male patients had better radiographic results than female patients, but not better functional scores. Medial meniscus and lateral meniscus results were not significantly different. Knees with a femoral-tibial anatomic alignment of > 0 degree valgus compared with < or = 0 degree and that had undergone medial meniscectomy had significantly better radiographic results. Patients with anterior cruciate ligament tears and meniscectomy did significantly poorer than stable knees with meniscectomy in regards to radiographic grade change, Lysholm, satisfaction index, Tegner level, and medial joint space narrowing.

Micropapillary serous carcinoma of the ovary. A distinctive low-grade carcinoma related to serous borderline tumors.

According to the International Federation of Gynecology and Obstetrics (FIGO) and the World Health Organization (WHO), stromal invasion, defined as destructive infiltrative growth, is the sole criterion used to distinguish serous borderline tumors from invasive serous carcinomas of the ovary. Although this criterion effectively identifies most malignant tumors, it does not permit the identification of a small subset of well-differentiated ovarian carcinomas that do not display destructive infiltrative growth but that may be associated with malignant behavior. In this study, we describe a group of such serous neoplasms that have distinctive morphologic features and that are often associated with progressive, invasive disease. We have designated these tumors micropapillary serous carcinomas (MPSC). They are characterized by a filigree pattern of highly complex micropapillae arising directly from large, bulbous papillary structures. The micropapillae are covered by round to cuboidal cells with a high nuclear-to-cytoplasmic ratio. Typical serous borderline tumors tend to display a hierarchical pattern of branching terminating in small papillae or tufts, and the cells covering the papillae tend to be more columnar and often ciliated compared with cells of MPSC. We reviewed more than 400 cases of serous ovarian borderline tumors and well-differentiated serous carcinomas and identified 26 cases of MPSC. Seventeen tumors lacked destructive infiltrative growth (noninvasive), and nine contained areas of invasion ranging from minimal to extensive. Eight of the 26 tumors were stage I, and none of the patients developed recurrence whether or not their tumors had demonstrable invasion. In contrast, of the 16 women presenting with stage II disease or higher and who had more than 1 year of follow-up, eight (50%) have either died of intra-abdominal carcinomatosis or are alive with carcinoma. Twenty-four (92%) of MPSCs contained areas of serous borderline tumor. The frequent association of MPSCs with serous borderline tumors suggests that MPSCs arise from the latter and may account for the few cases of serous borderline tumors that have been associated with progression to invasive carcinoma.

Comparison of anterior cruciate ligament reconstructions using patellar tendon autograft or allograft.

Seventy-eight of 113 consecutive patellar tendon anterior cruciate ligament reconstructions (autograft, 47 of 66; allograft, 31 of 47) were evaluated at an average of 34 months. Reconstructions were compared with Lysholm and Tegner knee-rating scales, physical examination findings, instrumented laxity values, single-leg hop distances, and isokinetic strength results. Lysholm scores > or = 90 were achieved by 69% of autograft patients versus 67% of allograft patients. Desired Tegner activity scores were achieved by 80% of autograft patients versus 74% of allograft patients. Patellofemoral signs and symptoms were absent in 40% of autograft patients versus 44% of allograft patients. Side-to-side laxity differences < or = 3 mm were achieved in 80% of autograft patients versus 70% of allograft patients. Single-leg hop scores > or = 90% of the nonoperated leg were obtained in 76% of autograft patients versus 81% of allograft patients. Isokinetic results between groups were also similar. Traumatic ruptures were sustained by four allograft patients at an average of 11 months postoperatively compared with no traumatic ruptures in the autograft group (P = .011). This was the only difference of statistical significance.

Short-term effects of knee washout for osteoarthritis.

Twenty-nine knees in 23 patients with symptomatic osteoarthritis underwent washout with lactated Ringer's solution. Two arthroscopic cannulas were placed into the knee under local anesthetic. Three liters of fluid were run through the knee using varying inflow and outflow to alternately inflate and deflate the knee. We obtained Hospital for Special Surgery knee scores, Knee Society pain and function ratings, and visual analog pain scales before washout and up to 2 years after washout. At 1 year, the mean Hospital for Special Surgery score increased from 72 to 87, the Knee Society pain rating from 64 to 89, and the Knee Society function rating from 62 to 82. Twenty-five knees had a good or excellent result at 1 year. Twenty-one of these were observed at 2 years; 17 had good or excellent results. This study confirms the value of a fluid washout in an arthritic knee for some patients. This may explain some of the symptom relief seen with arthroscopic procedures in this condition.

Lisfranc injuries in the athlete.

Injuries to the Lisfranc joint in the athlete comprise a very small proportion of tarsometatarsal injuries and are unique in several different ways. The energy involved appears to be on a much smaller order of magnitude than more commonly encountered injuries leading to obvious fracture and dislocation. Second metatarsal subluxation with diastasis between the first and second metatarsal tends to be the most commonly encountered injury; however, the true extent of injury cannot be based solely on the amount of diastasis present. Lateral weight-bearing radiographs facilitate evaluation of the normal medial cuneiform-fifth metatarsal relationship, which when disrupted indicates an injury more significant than a simple sprain and the possible need for open reduction and internal fixation. Finally, the restoration of this normal radiographic relationship between the medial cuneiform and fifth metatarsal on lateral weight-bearing views correlates well with the prognosis for achieving an asymptomatic, well-functioning foot, allowing a return to a competitive level of athletic participation.