Quadriceps strength asymmetry as predictor of ankle sprain in male volleyball players.

BACKGROUND: Ankle sprain is the most common acute time-loss injury in volleyball and occurs mainly during landing from a jump. Therefore, we have evaluated the role of quadriceps strength and countermovement jump height on ankle sprain occurrence, as these intrinsic modifiable risk factors were not yet evaluated. We have also hypothesized that presence of quadriceps strength asymmetry could be a possible risk factor for ankle sprains in male volleyball players. METHODS: This was a prospective cohort study. Male volleyball players (N.=99) from Slovenian national league participated in the study. Before the start of the season, all participants completed a preseason questionnaire and underwent evaluation of vertical jump performance and bilateral isokinetic strength of the quadriceps (Q) and hamstrings (H). During the subsequent season the players reported acute time loss injuries because of ankle sprain through a weekly questionnaire. RESULTS: We have registered 19 ankle sprains during the season. Overall ankle sprain incidence was 0.41±0.24 per 1000 h. Previous ankle sprain (Odds Ratio: 0.86; 95% CI: 0.25-2.89, P=0.802) and jump height (1.05; 95% CI: 0.94-1.19, P=0.393) were not significant risk factors, while Q strength asymmetry was a significant predictor of an ankle sprain (Odds Ratio: 0.956; 95% CI: 0.919-0.995, P=0.026). Compared with the uninjured players, the injured players had higher right concentric Q strength, higher Q strength asymmetry, and lower concentric right H-Q strength ratio (all P<0.03). CONCLUSIONS: Our results suggest that excessive concentric strength of the right Q, which leads to low H-Q strength ratio, and high bilateral Q strength asymmetry in favor of the right side, could be associated with increased risk of ankle sprains in male volleyball.

A model for potential non-contact ski injuries of the knee.

Broadly accepted is that most knee injuries result from increased vertical forces, usually induced by an incidental ski fall, collision, or a high jump. We present a new non-contact knee injury mechanism that can happen during a ski turn. Such an injury is governed by a sudden inward turn of the inner ski and consequent swing of the inner leg followed by a nearly instant stop when locked by hip and knee joints. The model provides predictive results for a lateral tibial plateau compression fracture because several simplifications have been made. We confirmed that the modelled compression stresses at typical skiing conditions and with typical skiing equipment can provoke serious knee injuries. The awareness of skiers and skiing equipment industry of the described knee injury mechanism can act as an important injury-prevention factor.

Minimally invasive reconstruction of the medial patellofemoral ligament using quadriceps tendon.

Reconstruction of the medial patellofemoral ligament (MPFL) for the treatment of patellar instability has received increased attention over the past few years. Most operative techniques use hamstring grafts fixed with bone tunnels and/or anchors on the patella. Despite good clinical results using these techniques, complications such as implant breakage, patellar fractures through bone tunnels, and loss of knee motion have occurred. We present a minimally invasive technique for MPFL reconstruction using a strip of quadriceps tendon. With the use of specially designed instruments, the graft is harvested through a 3-cm transverse incision at the proximal pole of the patella. The tendon strip is then dissected distally on the patella, left attached, and diverged 90° medially underneath the medial prepatellar tissue. The graft is fixed on the femur in 20° of knee flexion in a bone tunnel with a bioabsorbable interference screw (adults) or a bone anchor (children). We think that this technique presents a valuable alternative to common hamstring techniques for primary MPFL reconstruction in children and adults, as well as for MPFL revision surgery.

MPFL reconstruction using a quadriceps tendon graft: part 2: operative technique and short term clinical results.

BACKGROUND: We describe the preliminary clinical results of a new operative technique for MPFL reconstruction using a strip of quadriceps tendon (QT). PATIENTS: 17 patients (7 male, 10 female; mean age 21.5 years ± 3.9) have been operated on with this technique. All patients were evaluated clinically, radiologically and with subjective questionnaires (Tegner-, Lysholm-, Kujala Score) pre-operatively and post-operatively at 6 and 12 months (m). SURGICAL TECHNIQUE: A 10 to 12 mm wide, 3mm thick and 8 to 10 cm long strip from the central aspect of quadriceps tendon is harvested subcutaneously. The tendon strip is then dissected distally on the patella, left attached, diverged 90° medially underneath the medial prepatellar tissue and fixed with 2 sutures. The graft is fixed in 20° of knee flexion with a bioabsorbable interference screw. RESULTS: Lysholm score at 6m was 81.9 ± 11.7 and at 12 m 88.1 ± 10.9, Kujala score at 12 m was 89.2 ± 7.1 and Tegner Score was 4.9 ± 2.0 (6m) and 5.0 ± 1.9 (12 m). Two patients had a positive apprehension test at 12 months. There was no re-dislocation during the follow-up period. CONCLUSION: MPFL reconstruction with a strip of QT harvested in a minimal invasive technique was found to be associated with good short term clinical results. We think that this technique presents a valuable alternative to common hamstring techniques for primary MPFL reconstruction in children and adults, as well as for MPFL revision surgery. LEVEL OF EVIDENCE: IV, prospective case series.

Strength asymmetry of the shoulders in elite volleyball players.

CONTEXT: Volleyball players are reported to have shoulder strength imbalances. Previous authors have primarily investigated small samples of male players at a single skill level, without considering playing position, and with inconsistent findings. OBJECTIVE: To evaluate shoulder strength asymmetry and a history of shoulder injury in a large sample of professional volleyball players of both sexes across different playing positions and skill levels. DESIGN: Descriptive laboratory study. PATIENTS OR OTHER PARTICIPANTS: A sample of 183 volleyball players (99 men, 84 women). MAIN OUTCOME MEASURE(S): We assessed shoulder internal-rotator and external-rotator concentric strength at 60°/s using an isokinetic dynamometer and dominant-nondominant differences in shoulder strength and strength ratios using repeated-measures analyses of variance. Peak torque was normalized for body mass and external-rotation/internal-rotation concentric strength. RESULTS: Internal-rotation strength was asymmetric in favor of the dominant side in both sexes, regardless of previous shoulder injury status. Male volleyball players had a lower shoulder strength ratio on the dominant side, regardless of previous shoulder injury status. However, this finding was valid only when hand dominance was taken into account. Female volleyball players playing at a higher level (ie, first versus second division) were 3.43 times more likely to have an abnormal strength ratio. Playing position was not associated with an abnormal shoulder strength ratio or strength asymmetry. CONCLUSIONS: In male volleyball players, the external-rotation/internal-rotation strength ratio of the dominant shoulder was lower, regardless of playing position, skill level, or a previous shoulder injury. In female players, the ratio was less only in those at a higher skill level. Although speculative, these findings generally suggest that female volleyball players could have a lower risk of developing shoulder-related problems than male volleyball players. Isokinetic shoulder testing may reveal important information about the possible risk factors for shoulder injuries, so we recommend including it in the functional screening of volleyball players.

Knee temperatures measured in vivo after arthroscopic ACL reconstruction followed by cryotherapy with gel-packs or computer controlled heat extraction.

PURPOSE: To obtain in vivo data about intra- and extra-articular knee temperatures to assess the effectiveness of two cryotherapeutic methods-conventional cooling with gel-packs and computer controlled cryotherapy following anterior cruciate ligament (ACL) reconstructive surgery. METHODS: Twenty patients were arbitrarily assigned for cryotherapy after ACL reconstruction: 8 patients with frozen gel-packs and 12 patients with computer controlled cryotherapy with constant temperatures of the cooling liquid in the knee pads. The treatment was performed for 12 h. Temperatures were measured with two thermo sensors in catheters placed intraarticularly and subcutaneously, four sensors on the skin and one sensor under protective bandage, every second for 16 h after surgery. RESULTS: In the first 2 h of treatment, there were no significant differences (n.s.) between the groups in temperatures in the intracondylar notch. After 4 h of cryotherapy, the temperatures were significantly lower on the skin (24.6 ± 2.8 and 31.4 ± 1.3 °C, p < 0.01) and in the subcutaneous tissue (28.6 ± 5.7 and 34.6 ± 1.4 °C, p = 0.01), and the difference between the temperature in the intracondylar notch and the subcutaneous tissue was significantly greater (4.0 ± 3.0 and 0.8 ± 0.6 °C, p = 0.01) in the computer controlled cryotherapy group compared to the gel-pack group. CONCLUSIONS: The cooling effect of the arthroscopy irrigation fluid on the knee temperature is evident in the first 2 h of treatment. The energy extraction is significantly more effective and controllable by computer controlled cryotherapy than with frozen gel-packs. LEVEL OF EVIDENCE: Prospective comparative study, Level II.

Simultaneous reconstruction of ruptured anterior cruciate ligament and medial patellofemoral ligament with ipsilateral quadriceps grafts.

Rupture of the anterior cruciate ligament is a well-known entity and causes anteroposterior and rotational instability of an injured knee. Rupture of the medial patellofemoral ligament is less frequent, and its insufficiency causes patellar instability. Several techniques have been described for the reconstruction of each ligament. The 2 lesions and following instabilities can coexist, and both ligaments can be reconstructed simultaneously. We report on 2 cases, 1 recreational sportswoman and 1 high-level sportswoman, with coexisting lesions treated surgically by a single-step procedure using ipsilateral graft of the quadriceps tendon for reconstruction of medial patellofemoral ligament and anterior cruciate ligament. The advantage of this procedure is that there is only 1 donor site, and thus lower donor-site morbidity, while the strength of either neoligament is not sacrificed. The technique is described here.

Computer simulation of topical knee cooling.

Local topical cooling with gel-packs or cryo-cuffs is often used after surgery or after knee injuries. Mostly beneficial, but some deleterious effects have been reported in literature. The spatial distribution of heat/cold through different tissues of the knee in time may be responsible for different effects of cooling on the traumatized or inflamed tissue and have yet to be studied. Parallel computer simulation was used to study, non-invasively, temperature changes in the knee during cooling. A 3-D computer model of the knee, with a spatial resolution of 1mm, was derived from cross sections available in the visible human dataset. Heat transfer in a non-homogenous knee tissue was modeled with a diffusion equation, which was solved by the explicit finite difference method. The heat transfer between blood and tissue and tissue metabolism have also been modeled and simulated. Two different simulations were performed: cooling with a liquid at constant temperature (cryo-cuff) and topical cooling with frozen gel-packs. The simulated results were analyzed and compared with relevant measurements.

Endoscopic evacuation of a hematoma resulting from strain injury of the medial head of the gastrocnemius muscle.

Strain of the medial head of the gastrocnemius muscle (GM) is a common injury that can be confirmed by ultrasound (US) or magnetic resonance imaging. We report a case of strain injury of the medial head of the GM, with a hematoma between the soleus muscle and the GM. US revealed an enlarged hypoechoic area between the soleus and the GM. By US-guided puncture, only a small amount of old blood was evacuated. Hence we undertook a surgical approach. It was performed under general endotracheal anesthesia, in the prone position. The most superficial area of hematoma was shown by US. A sharp 4-mm trocar was inserted in the posteromedial side of the calf and the hematoma was partially evacuated by suction. The cavity was washed out with saline solution. The arthroscope was then inserted. A second portal was made laterally and a shaver was inserted under optic control. The inflow pressure was not allowed to exceed 45 mm Hg. The shaver was used to remove blood coagula and fibrin septa that divided the cavity. The fibrous cavity membrane was debrided. By the end of the procedure, the circumference of the leg was reduced by 3 cm and the skin was softer on palpation. The patient was discharged the next day. One week after surgery, US examination revealed only a thin hypoechoic area in place of the previous collection. Two weeks after surgery, he was able to walk painlessly, and at 6 weeks he had regained normal walking activity.

Intraarticular patient-controlled regional anesthesia after arthroscopically assisted anterior cruciate ligament reconstruction: ropivacaine/morphine/ketorolac versus ropivacaine/morphine.

UNLABELLED: Anterior cruciate ligament reconstruction (ACLR) is associated with moderate to severe postoperative pain. We compared the intraarticular analgesic effects of ropivacaine and morphine with or without ketorolac and the need for rescue IV morphine at rest and during movement in patients undergoing anterior cruciate ligament reconstruction during spinal anesthesia. Thirty-nine patients receiving intraarticular patient-controlled regional analgesia with a 10-mL bolus and a 60-min lockout interval were randomized into 3 groups: the RM group received 0.25% ropivacaine and morphine 0.2 mg/mL; the RMK group received 0.25% ropivacaine, morphine 0.2 mg/mL and ketorolac 1 mg/mL; the P group received saline. Analgesic mixtures were prepared in 100-mL bags and coded. If needed, rescue morphine 2 mg was self-administered IV with 10-min lockout intervals. Pain scores and patient satisfaction were assessed at rest and during movement. There were no significant differences among the groups in pain scores and patient satisfaction. Daily morphine consumption was significantly smaller in the RMK group (8 +/- 8 mg) compared with the RM group (23 +/- 20 mg; P = 0.002) and in both groups compared with control (46 +/- 21 mg; P < 0.001). We conclude that intraarticular patient-controlled regional analgesia provides effective pain relief after anterior cruciate ligament reconstruction. The combination of intraarticular ropivacaine, morphine, and ketorolac was superior to control or to a combination of ropivacaine and morphine. IMPLICATIONS: This study showed the feasibility and efficacy of intraarticular patient-controlled regional analgesia technique for pain relief after anterior cruciate ligament reconstruction. The combination of intraarticular ropivacaine, morphine, and ketorolac was superior to control or to a combination of ropivacaine and morphine.

Inferior patellar pole avulsion fractures: osteosynthesis compared with pole resection. Surgical technique.

BACKGROUND: The ideal treatment for avulsion fractures of the inferior pole of the patella has not yet been identified. The options include (1) internal fixation of the pole fragment and (2) resection of the avulsed fragment and repair of the patellar ligament to the patella. We are not aware of any previous study in which the results of internal fixation have been compared with those of pole resection. The purpose of the present study was to compare the long-term results of internal fixation (with use of a basket plate) with those of pole resection. METHODS: We retrospectively studied two groups of patients who had had operative treatment of an avulsion fracture of the inferior patellar pole between 1990 and 1997. Fourteen patients had had internal fixation with a basket plate, and fourteen had had pole resection with patellar ligament repair. Eleven patients who had had internal fixation (Group A) and thirteen patients who had had pole resection (Group B) were followed for an average of 4.6 years. The final evaluation was based on the patellofemoral score, and the patellar height was measured radiographically. RESULTS: The average patellofemoral score (maximum, 100 points) was 94.1 points in Group A and 81.2 points in Group B. Significant differences between the groups were noted with regard to knee pain, level of activity, and range of motion. Normal patellar height was found in ten of eleven patients in Group A and in three of thirteen patients in Group B. Patella baja was significantly associated with a poor functional outcome. CONCLUSIONS: In patients who have sustained an avulsion fracture of the inferior patellar pole, the normal height of the patella can be maintained by preserving the patellar pole. In contrast with pole resection, which requires postoperative immobilization, internal fixation with a basket plate allows for immediate mobilization and early weight-bearing. The present study indicates that internal fixation with use of a basket plate can provide better clinical results.

Inferior patellar pole avulsion fractures: osteosynthesis compared with pole resection.

BACKGROUND: The ideal treatment for avulsion fractures of the inferior pole of the patella has not yet been identified. The options include (1) internal fixation of the pole fragment and (2) resection of the avulsed fragment and repair of the patellar ligament to the patella. We are not aware of any previous study in which the results of internal fixation have been compared with those of pole resection. The purpose of the present study was to compare the long-term results of internal fixation (with use of a basket plate) with those of pole resection. METHODS: We retrospectively studied two groups of patients who had had operative treatment of an avulsion fracture of the inferior patellar pole between 1990 and 1997. Fourteen patients had had internal fixation with a basket plate, and fourteen had had pole resection with patellar ligament repair. Eleven patients who had had internal fixation (Group A) and thirteen patients who had had pole resection (Group B) were followed for an average of 4.6 years. The final evaluation was based on the patellofemoral score, and the patellar height was measured radiographically. RESULTS: The average patellofemoral score (maximum, 100 points) was 94.1 points in Group A and 81.2 points in Group B. Significant differences between the groups were noted with regard to knee pain, level of activity, and range of motion. Normal patellar height was found in ten of eleven patients in Group A and in three of thirteen patients in Group B. Patella baja was significantly associated with a poor functional outcome. CONCLUSIONS: In patients who have sustained an avulsion fracture of the inferior patellar pole, the normal height of the patella can be maintained by preserving the patellar pole. In contrast with pole resection, which requires postoperative immobilization, internal fixation with a basket plate allows for immediate mobilization and early weight-bearing. The present study indicates that internal fixation with use of a basket plate can provide better clinical results.

Posterior approach for arthroscopic reduction and antegrade fixation of avulsion fracture of the posterior cruciate ligament from the tibia with cannulated screw and washer.

Avulsion fracture of the posterior cruciate ligament (PCL) is a rare condition, and arthroscopically assisted reattachment of the surgical fixation of the fragment is not always an easy task. Only a few reports describe techniques for arthroscopic fixation of avulsion of the PCL.We report on a case treated arthroscopically with reduction and antegrade fixation of an avulsion fracture of the tibial attachment of the PCL with a cannulated screw and washer through an additional posterolateral portal. Postoperative morbidity was reduced, and rehabilitation was accelerated. Fixation with a cannulated screw and washer is technically simple and allows for stable fixation and immediate postoperative mobilization and pain-limited weight-bearing, even in cases of a comminuted fragment. The safe zone for an additional posterolateral portal and the technique for placing instruments and a guidewire to avoid neurovascular structures is defined.

Anterograde arthroscopic fixation of avulsion fractures of the tibial eminence with a cannulated screw: five-year results.

PURPOSE: Fractures of the tibial eminence can be treated arthroscopically. Fixation of the fracture is usually followed by temporary immobilization. The literature suggests that only anterograde fixation with cannulated screws and washer is considered stable enough to allow for immediate mobilization and weight bearing. The goal of this study was to evaluate the 5-year results of arthroscopic reductions and anterograde fixations of the tibial eminence fracture with cannulated screws. TYPE OF STUDY: Retrospective study. METHODS: Thirty-two patients were treated arthroscopically for type II, III, and IV fractures of the intercondylar eminence of the tibia. The fragments were reduced and fixed with a cannulated screw or cannulated screw and washer. The intermeniscal ligament was involved in the fracture in 29 cases, and the anterior part of the medial meniscus was involved in 3 cases, requiring a temporary shift before reduction of the fragment. Arthrotomy was not performed for reduction or fixation of the fragment. All patients began continuous passive and active motion of the involved knee and were mobilized on crutches the day after the procedure. They were allowed immediate weight bearing. The patients were followed up for 16 to 69 months. RESULTS: Good therapeutic results were found at follow-up. Average value for KT-1000 testing was 1.1 mm; flexion deficit was 1.2 degrees; extension deficit, 0.6 degrees; and Lysholm score, 98.8. The average treatment duration was 12 weeks. There was one case of aseptic synovitis and no other complications. In all but 1 patient, the implants were removed. CONCLUSIONS: Arthroscopic fixation of the fracture of the intercondylar eminence of the tibia with a cannulated screw or screw and washer is a simple, safe, reproducible, and effective procedure. The fixation is stable even in type IV fractures, so that immobilization is unnecessary.