W. Andrew Eglseder

Autografts from the foot for reconstruction of the scapholunate interosseous ligament.

A cadaveric study was undertaken to identify a potential autograft for use in repairing the ruptured scapholunate interosseous ligament. Three ligament complexes (the dorsal metatarsal ligament of the fourth and fifth metatarsals, a dorsal tarsometatarsal ligament, and the dorsal calcaneocuboid ligament) were chosen as autograft candidates. The scapholunate interosseous ligament and the three autograft candidates were harvested as bone-ligament-bone complexes from matched hands and feet of six fresh-frozen male cadavers (age, 51-68 years). The complexes were elongated using a servohydraulic testing machine at a constant grip-to-grip rate of 0.1 mm/s until failure. Stiffness and strength values were calculated and compared for each ligament complex. Analysis indicated that the stiffness values for the tarsometatarsal ligament and the scapholunate interosseous ligament were not statistically different, while such values for the other two autografts were significantly less. The strength values of all three autografts were significantly less than those of the scapholunate interosseous ligament. This study indicates that of the potential autografts tested, the tarsometatarsal ligament is biomechanically most similar to the intact scapholunate interosseous ligament.

Are locking screws advantageous with plate fixation of humeral shaft fractures? A biomechanical analysis of synthetic and cadaveric bone.

Objectives: To investigate whether locking screws offer any advantage over nonlocking screws for plate fixation of humeral shaft fractures for weight-bearing applications. Design: Mechanical evaluation of stiffness in torsion, bending, and axial loading and failure in axial loading in synthetic and cadaveric bone. Setting: Biomechanical laboratory in an academic medical center. Methods: We modeled a comminuted midshaft humeral fracture in both synthetic and cadaveric bone. Humeri were plated posteriorly. Two study groups each used identical 10-hole, 3.5-mm locking compression plates that can accept either locking or nonlocking screws. The first group used only nonlocking screws and the second only locking screws. Stiffness testing and failure testing were performed for both the synthetic bones (n = 6) and the cadaveric matched pairs (n = 12). Fatigue testing was set at 90,000 cycles of 440 N of axial loading. Main Outcome Measures: Torsion, bending, and axial stiffness and axial failure force after cyclic loading. Results: With synthetic bones, no significant difference was observed in any of the 4 tested stiffness modes between the plates with locking screws and those with nonlocking screws (anteroposterior, P = 0.51; mediolateral, P = 0.50; axial, P = 0.15; torsional, P = 0.08). With initial failure testing of the constructs in axial loading, both plates failed above anticipated physiologic loads of 440 N (mean failure load for both constructs >4200 N), but no advantage to locking screws was shown. The cadaveric portion of the study also showed no biomechanical advantage of locking screws over nonlocking screws for stiffness of the construct in the 4 tested modes (P > 0.40). Fatigue and failure testing showed that both constructs were able to withstand strenuous fatigue and to fail above anticipated loads (mean failure >3400 N). No difference in failure force was shown between the 2 groups (P = 0.67). Conclusions: Synthetic and cadaveric bone testing showed that locking screws offer no obvious biomechanical benefit in this application.

Concurrent dorsal dislocations and fracture-dislocations of the index, long, ring, and small (second to fifth) carpometacarpal joints.

Objective To review the outcome of patients with concurrent dorsal dislocations and fracture-dislocations of the second, third, fourth, and fifth carpometacarpal (CMC) joints treated with open reduction and internal fixation (ORIF). Design Retrospective review. Setting Level 1 trauma center. Patients Between 1991 and 1997, twelve multiply injured patients with the described CMC injury complex (one open injury) were treated with ORIF (eleven patients) or percutaneous wire fixation (one patient) by the same surgeon. Intervention Treatment consisted of ORIF with Kirschner wires followed by splints and immediate metacarpophalangeal and interphalangeal joint range of motion exercises. Main Outcome Measurements Grip strength, wrist and finger range of motion, pain, need for additional surgery, and return to work. Results Of the ten patients available for follow-up (mean, three years), all had been treated with ORIF (eight within forty-eight hours of injury and two had treatment delayed for four weeks because of delayed diagnosis and management of more serious injuries). Three patients had additional surgery (planned secondary second and third CMC arthrodeses). Grip strength of the operated hand in the five patients with JAMAR testing was 50 percent (n = 3), 75 percent (n = 1), and 90 percent (n = 1) of that in their contralateral hands. Five patients were pain-free, and five reported occasional, activity-related pain. The five patients who worked before the injury returned to their previous occupations (one with slightly modified duties). Conclusion This is the largest series of patients with this CMC injury complex and the first report of open CMC dorsal dislocations and fracture-dislocations. Although early ORIF is suggested, delay of up to four weeks did not adversely affect results.

A review of outcomes in 18 patients with floating elbow

Objective To assess functional outcomes and predictors of success in floating elbow injuries. Design Retrospective clinical review. Setting Level 1 trauma center. Patients Eighteen patients with floating elbow injuries seen at the trauma center from 1995–2001. Intervention All injuries were managed surgically. Each forearm fracture was managed with open reduction and internal fixation. Humerus fractures were managed with either open reduction and internal fixation or intramedullary nail. Definitive fixation was performed in all cases within 48 hours of arrival at the trauma center. Main Outcome Measurements Eighteen patients were available for follow-up at a minimum of 1 year and consented to enroll in the study. Each patient was evaluated with a standardized elbow score based on a 100-point scale. These scores were correlated with injury features including age, severity of fracture (AO classification), open fractures, nerve injuries, vascular injuries, type of fixation on the humerus, and the presence of concomitant intra-articular elbow injuries. Results The average elbow score was 68/100. Outcomes were divided into two groups. Eleven patients had a score greater than 75 (group I), with a mean score of 83, and were considered to have a good or excellent result. Seven patients had a score less than 75 (group II), with a mean score of 45, and were considered to have a satisfactory or poor result. The distribution of outcomes revealed two statistically distinct clusters. Additionally, there was a significantly higher incidence of nerve injuries in group 2 compared with group 1. Conclusions Functional outcomes in floating elbow injuries tend to cluster into two groups—patients with good or excellent results and patients with poor results. Patients with associated nerve injuries have lower functional outcomes at a minimum of 1-year follow-up.

Monteggia fractures and variants: review of distribution and nine irreducible radial head dislocations.

One hundred and twenty one cases of Monteggia fractures (68) and Monteggia fracture equivalent variant transolecranon fracture dislocations (53) in adults were reviewed to determine the frequency of Bado types and the occurrences of irreducible radial head dislocations. The distribution of Monteggia fractures was 53 Bado type I, two Bado type II, eight Bado type III, and five Bado type IV. Nine (13%) irreducible radial head dislocations were encountered (8 in Bado type I fractures and one in Bado type IV), including an unreported occurrence of biceps tendon interposition. The distribution in the Monteggia variants was 35 Bado type I, 14 Bado type II, one Bado type III, and two Bado type IV, without any irreducible radial heads. The present study demonstrates a greater preponderance of Bado type I than any other type among adult Monteggia fractures.

Type IV flexor digitorum profundus avulsion

Flexor digitorum profundus avulsions, are well-documented injuries occasionally associated with a distal phalanx fragment. While the injury may involve primarily either tendon or bone, a rarely observed variant combines both tendon and bone avulsions. A type IV variant seen after two sequential injuries is described.

Do one-time intracompartmental pressure measurements have a high false-positive rate in diagnosing compartment syndrome?

BACKGROUND Intracompartmental pressure measurements are frequently used in the diagnosis of compartment syndrome, particularly in patients with equivocal or limited physical examination findings. Little clinical work has been done to validate the clinical use of intracompartmental pressures or identify associated false-positive rates. We hypothesized that diagnosis of compartment syndrome based on one-time pressure measurements alone is associated with a high false-positive rate. METHODS Forty-eight consecutive patients with tibial shaft fractures who were not suspected of having compartment syndrome based on physical examinations were prospectively enrolled. Pressure measurements were obtained in all four compartments at a single point in time immediately after induction of anesthesia using a pressure-monitoring device. Preoperative and intraoperative blood pressure measurements were recorded. The same standardized examination was performed by the attending surgeon preoperatively, postoperatively, and during clinical follow-up for 6 months to assess clinical evidence of acute or late compartment syndrome. RESULTS No clinical evidence of compartment syndrome was observed postoperatively or during follow-up until 6 months after injury. Using the accepted criteria of delta P of 30 mm Hg from preoperative diastolic blood pressure, 35% of cases (n = 16; 95% confidence interval, 21.5–48.5%) met criteria for compartment syndrome. Raising the threshold to delta P of 20 mm Hg reduced the false-positive rate to 24% (n = 11; 95% confidence interval, 11.1–34.9%). Twenty-two percent (n = 10; 95% confidence interval, 9.5–32.5%) exceeded absolute pressure of 45 mm Hg. CONCLUSION A 35% false-positive rate was found for the diagnosis of compartment syndrome in patients with tibial shaft fractures who were not thought to have compartment syndrome by using currently accepted criteria for diagnosis based solely on one-time compartment pressure measurements. Our data suggest that reliance on one-time intracompartmental pressure measurements can overestimate the rate of compartment syndrome and raise concern regarding unnecessary fasciotomies. LEVEL OF EVIDENCE Diagnostic study, level II.

Articular cartilage thickness at the distal radius: a cadaveric study.

PURPOSE Articular stepoffs that occur after fracture and are greater in size than the thickness of the articular surface seem to result in arthritis. The thickness of a joints cartilage may, therefore, set the limit for acceptable stepoff when treating fractures. The goal of our study was to determine the thickness of the articular cartilage at the distal radius. METHODS We conducted a cadaveric study of 19 wrists to measure the thickness of cartilage at the distal radius. After harvest, we made multiple slices of each radius and used a standardized technique to directly measure the articular cartilage in the scaphoid and lunate fossae and along the interfossal ridge. RESULTS The average cartilage thickness in our cohort was 0.6 mm. The average articular surface thickness was < 1 mm in all measured areas (scaphoid fossa, 0.7 mm; interfossal ridge, 0.8 mm; lunate fossa, 0.6 mm). Among the samples, 98% had an average thickness of < 1 mm. The maximum recorded thickness was 1.1 mm. CONCLUSIONS Our study quantifies the thickness of the articular cartilage at the distal radius. Our finding of cartilage thicknesses of < 1 mm is consistent with multiple clinical studies, suggesting that stepoffs of > 1 mm result in radiographic signs of arthritis. This provides further evidence linking the thickness of articular cartilage to radiographic outcomes and, possibly, clinical outcomes. CLINICAL RELEVANCE Our findings provide anatomic support for using 1 mm or less as an acceptable articular stepoff size in the treatment of fractures of the distal radius.

Salvage of functional elbow range of motion in complex open injuries using a sensate transposition lateral arm flap

Complex open posterior elbow injuries pose three principal challenges to the reconstructive surgeon. First, the surgeon must provide stable soft-tissue closure over the joint/skeletal reconstruction. Second, the coverage must be thin and supple and promote the free gliding of the underlying structures. Finally, secondary and tertiary procedures must be anticipated beneath the flap, because a stiff, scarred, and adherent flap will only compromise these procedures. The results of 10 consecutive fasciocutaneous transposition lateral arm flaps for coverage of posterior elbow wounds are reported. This flap provides coverage that is thin and supple and that allows subsequent elevation for secondary procedures. Functionally, these flaps allowed for the development of an average arc of motion of 20 to 114 degrees and an average pronation-supination motion of 119 degrees.

Use of 2 column screws to treat transcondylar distal humeral fractures in geriatric patients.

We describe fixation of transcondylar distal humeral fractures with column screws in geriatric patients and review our initial results. We conducted a retrospective review of a prospectively collected database at a Level I trauma center. Six patients met inclusion criteria of age older than 65 years and treatment of minimally or nondisplaced transcondylar distal humeral fracture with column screws only. All were closed fractures with no associated nerve injuries. One patient was lost to follow-up. The mechanism of injury was low-energy fall for the 5 remaining patients (average age, 74 y; age range, 70 to 83 y; average follow-up duration, 10.6 wk). One patient had a traumatic brain injury and a contralateral metacarpal fracture that was treated with internal fixation. The remaining 4 patients sustained isolated distal humeral fractures. No complications were noted, and all fractures healed at an average radiographic union time of 7.2 weeks. Average range of motion was 22 degrees extension [95% CI (−1.47, 45.47)], 114 degrees flexion [95% CI (89.4, 138.6)], and 92 degrees arc of motion [95% CI (58.68, 125.38)]. Treatment of select transcondylar distal humeral fractures with column screws in geriatric patients provides an option for stable fixation that allows early range of motion with minimal surgical morbidity.