L. Joseph Rubino

Predictors for Hamstring Graft Diameter in Anterior Cruciate Ligament Reconstruction

Background The ability to accurately predict the diameter of autograft hamstring tendons has implications for graft choice and fixation devices used in anterior cruciate ligament (ACL) reconstruction. Purpose To determine whether simple anthropometric measurements such as height, mass, body mass index (BMI), age, and gender can be used to accurately predict the diameter of hamstring tendons for ACL reconstruction surgery. Study Design Cohort study (prevalence); Level of evidence, 2. Methods The authors conducted medical record reviews and telephone interviews of 106 consecutive patients with ACL reconstruction using quadrupled semitendinosus-gracilis autograft from 2004 to 2006. Data included anthropometric measurements (height, mass, gender, and age at the time of surgery). Hamstring diameter was obtained using cylindrical sizers in 0.5-mm increments and recorded in the patients surgical record. Correlation coefficients (Pearson r) and stepwise, multiple linear regression were used to determine the relationship between the outcome variable (hamstring graft diameter) and the predictor variables (age, gender, height, mass, and BMI). Independent sample t tests were used to compare hamstring graft diameter between genders. Results Hamstring graft diameter was related to height (r = .36, P < .001), mass (r = .25, P = .005), age (r = —.16, P = .05), and gender (r = —.24, P = .006) but was not related to BMI (P > .05). Height was a statistically significant prediction variable (R2 = .13, P < .001). From the current data, a regression equation was calculated that suggested that a patient <147 cm (58 in) tall is likely to have a quadrupled hamstring graft diameter <7 mm in diameter (graft size = 2.4 + 0.03 × height in cm). Women had significantly smaller hamstring graft diameters (7.5 ± 0.7 mm) than did men (7.9 ± 0.9 mm, P = .01). Conclusions Of the parameters studied, height was the best predictor of hamstring tendon diameter, particularly in women.

Distal-third clavicle fracture fixation: a biomechanical evaluation of fixation.

BACKGROUND Approximately 25% of distal clavicle fractures are unstable. Unstable patterns have longer times to union and higher nonunion rates. Stable restoration of the distal clavicle is important in decreasing the nonunion rate in distal clavicle fractures. The purpose of this study was to biomechanically compare operative constructs for the treatment of unstable, comminuted distal-third clavicle fractures in a cadaveric model using a locking plate and coracoclavicular reconstruction. We hypothesized that the combination of coracoclavicular reconstruction and a distal clavicle locking plate is biomechanically superior to either construct used individually. MATERIALS AND METHODS An unstable distal clavicle fracture was created in 21 thawed fresh-frozen cadaveric specimens. The 21 specimens were divided into 3 treatment groups of 7: distal-third locking plate, acromioclavicular (AC) TightRope (Arthrex, Naples, FL, USA), and distal-third locking plate and AC TightRope together. After fixation, each specimen was cyclically tested with recording of displacement to determine the stiffness and stability of each construct, followed by load-to-failure testing in tension and compression to determine the maximum load. RESULTS The combined construct of the locking distal clavicle plate and coracoclavicular reconstruction resulted in increased stiffness, maximum resistance to compression, and decreased displacement compared with either construct alone. CONCLUSION Greater fracture stability was achieved with the combination of the AC TightRope and locking clavicle plate construct than with either alone, suggesting a possibility for increased fracture-healing rates.

Fatty Infiltration Does Not Progress After Rotator Cuff Repair in a Rabbit Model

PURPOSE The purpose of this study is to evaluate the changes in fatty infiltration of the rotator cuff after it is repaired. METHODS The supraspinatus muscle was unilaterally detached from the greater tuberosity in 15 New Zealand white rabbits. Six weeks after muscle detachment, 5 rabbits were killed to halt the process of fatty infiltration and 10 rabbits underwent primary repair of the rotator cuff. Six months after repair, the remaining 10 rabbits were killed, and the muscle specimens were examined microscopically to evaluate the muscle with respect to fatty infiltration. RESULTS Fatty infiltration was evident 6 weeks after detachment of the supraspinatus tendon (P = .0012, analysis of variance). This infiltration was greatest at the musculotendinous junction (P = .0005) and decreased toward the muscle origin (P = .29). Six months after repair of the supraspinatus, there was no progression of fatty infiltration in the repaired muscle as compared with the controls (P = .3). CONCLUSIONS Fatty infiltration of the rotator cuff in this animal model occurs as early as 6 weeks after a rotator cuff tear. After repair of the rotator cuff, the process of fatty infiltration does not progress any further. The changes that take place in this rabbit model in the first 6 weeks after a rotator cuff tear appear to be irreversible even with successful rotator cuff repair. CLINICAL RELEVANCE The presence of fatty infiltration of a torn rotator cuff does not preclude a successful repair. The repair can prevent further progression and atrophy of the rotator cuff, but the changes that appear in the muscle as early as 6 weeks after a rotator cuff tear appear to be irreversible.

Joint infection unique to hamstring tendon harvester used during anterior cruciate ligament reconstruction surgery.

Joint infection after anterior cruciate ligament (ACL) reconstruction is a rare but important clinical issue that must be resolved quickly to prevent secondary joint damage and preserve the graft. After careful analysis, we observed 3 infection cases within a 12-month period after ACL reconstruction, which represented an abnormally elevated risk. All reconstructions were performed by the same surgeon and used hamstring tendon allograft. For each surgery, the Target Tendon Harvester (DePuy Mitek, Raynham, MA) was used to harvest hamstring tendons. Through our review, we learned that this instrument was sterilized while assembled. It is our belief that ineffective sterilization of this hamstring graft harvester served as the origin for these infections. We have determined that appropriate sterilization technique involves disassembly of this particular hamstring tendon harvester before sterilization because of the tube-within-a-tube configuration. We have since continued to use the Target Tendon Harvester, disassembling it before sterilization. There have been no infections in the ensuing 12 months during which the surgeon performed over 40 primary ACL reconstructions via hamstring autograft. The information from this report is intended to provide arthroscopists with information about potential sources of infection after ACL reconstruction surgery.

Healing of Iatrogenic Skeletal Muscle Wounds Is Affected by Incision Device

Orthopedic joint procedures frequently require extensive dissection of skeletal muscles resulting in tissue injury, formation of scar tissue, pain, and potentially, functional impairment. The authors hypothesized that using a low-temperature ultrasonic cutting and coagulating device (Harmonic Blade, Ethicon Endo-Surgery, Cincinnati, OH) would result in reduction in tissue trauma in terms of reducing acute and chronic inflammation during healing. Bilateral longitudinal incisions were made into the tibialis cranialis muscles of rabbits with either a Harmonic Blade or a standard monopolar electrosurgical scalpel. At 3, 7, and 21 days postoperatively, necropsy and histological evaluations indicated a significant attenuation of acute inflammation (P = .011) for the Harmonic incisions compared with electrosurgery. No significant differences were observed for chronic inflammation, necrosis, or fibrosis. Use of a Harmonic scalpel during dissection of skeletal muscle in orthopedic surgery may result in reduced influx of neutrophils, reducing acute inflammation, and potentially aid in reducing postoperative pain and functional impairment.

Glenohumeral Range of Motion and Lower Extremity Flexibility in Collegiate-Level Baseball Players

Background: The throwing motion results in unilateral increases in dominant arm external rotation (ER) range of motion (ROM). Trunk forward tilt at ball release is related to ball velocity. The relationship between lower quarter flexibility and dominant arm ROM is not known. Hypothesis: There is a relationship between lower extremity flexibility and dominant arm ER ROM and total rotation ROM. Study Design: Prospective cohort study. Methods: Forty-two collegiate baseball pitchers were studied. Demographics, dominant arm, and bilateral glenohumeral ER and internal rotation (IR) ROM were measured. Lower quarter flexibility was assessed via sit-and-reach test. Total rotation motion (TRM) was calculated as ER + IR = TRM. Paired t tests examined differences between the dominant and nondominant arms for ER, IR, and TRM; Pearson product-moment correlation coefficients, shoulder ROM and lower extremity flexibility variables (α = 0.05). Results: ER mean value was significantly greater, and IR mean value significantly less, in the dominant arm. TRM mean values were not significantly different bilaterally. Sit-and-reach results were strongly correlated with TRM and ER of the dominant arm. Conclusions: There was a significant shift in TRM toward ER in collegiate baseball players. Lower quarter flexibility was strongly correlated with dominant arm ER and total rotation ROM but not in the nondominant arm. Clinical Relevance: The sit-and-reach test may be useful to identify a pitcher’s potential to achieve an appropriate amount of trunk forward tilt. This may maximize the lag effect necessary to achieve maximum ER of the dominant arm and increased ball velocity.

Rabbit supraspinatus motor endplates are unaffected by a rotator cuff tear.

Rotator cuff tears are a major cause of morbidity. Following rotator cuff tears, muscle atrophy and fatty infiltration begin in the tissue, limiting repair potential and leading to a higher re‐tear rate and a worse functional outcome. We evaluated whether fatty degeneration resulting from a complete supraspinatus tear with retraction is associated with an injury to the suprascapular nerve. Four skeletally mature New Zealand white rabbits were randomized to receive an index procedure on either their right or left shoulder with the opposite shoulder serving as a control. At the index procedure, the supraspinatus tendon was transected at its insertion and allowed to retract. At 3 months, the rabbits were euthanized, and both supraspinatus muscles were harvested. The specimens were then examined with confocal microscopy and histology. Atrophy was grossly visible in all four test muscles, and fatty infiltration was confirmed with osmium tetroxide staining. In all four rabbits, the degree of denervation (p = 0.71) and partial denervation (p = 0.91) was not significantly different between control and experimental muscle. Rotator cuff tear does not affect the motor endplate or innervation status of the supraspinatus. Fatty infiltration occurs independent of denervation of the supraspinatus.

Subluxation of the sternoclavicular joint secondary to pseudarthrosis of the first and second ribs. A case report.

Anterior subluxation of the sternoclavicular joint is an uncommon but well-documented orthopaedic condition. It rarely occurs spontaneously in adolescents, and it usually has a benign clinical course, resolving when treated by rehabilitation and skillful neglect1,2. Occasionally, the subluxation may be caused by an underlying congenital condition. In this report, we present the case of a patient who had spontaneous subluxation of the sternoclavicular joint secondary to pseudarthrosis of the first and second ribs. A fourteen-year-old girl presented with a painful right sternoclavicular joint with no history of trauma. She first noted the discomfort when she was participating in marching-band activities at school, but it progressed to the point where it was elicited by activities of daily living. Physical examination revealed prominence of the medial aspect of the right clavicle, which was symptomatic on palpation ( Fig. 1 ). The sternoclavicular joint could not be reduced manually and was not clinically mobile. The patient had no neurologic or vascular compromise on provocative testing. She was treated with restriction of activity, nonsteroidal anti-inflammatory medications, and physical therapy. After six months of treatment, she still had pain, and a computed tomographic …