Bracing can partially limit tibial rotation during stressful activities after anterior crucial ligament reconstruction with a hamstring graft.

BACKGROUND: Hamstring graft has substantial differences with BPTB graft regarding initial mechanical strength, healing sequence, and vascularization, which may imply that a different approach during rehabilitation period is required. The purpose of this study was to investigate the influence of knee bracing on tibial rotation in ACL-reconstructed patients with a hamstring autograft during high loading activities. The hypothesis was that there would be a decrease in tibial rotation in the ACL-reconstructed braced knee as compared to the unbraced knee. METHODS: Twenty male patients having undergone unilateral ACL reconstruction with a semitendinosus/gracilis autograft were assessed. Kinematic data were collected with an eight-camera optoelectronic system during two stressful tasks: (1) descending from a stair and subsequent pivoting; and (2) landing from a platform and subsequent pivoting. In each patient, three different experimental conditions were evaluated: (A) wearing a prophylactic brace (braced condition); (B) wearing a patellofemoral brace (sleeved condition); (C) without brace (unbraced condition). The intact knee without brace served as a control. RESULTS: Tibial rotation was significantly lower in the intact knee compared to all three conditions of the ACL-reconstructed knee (P≤0.01 for both tasks). Presence of a brace or sleeve resulted in lower tibial rotation than in the unbraced condition (p=0.003 for descending/pivot and P=0.0004 for landing/pivot). The braced condition resulted in lower rotation than the sleeved condition for descending/pivoting (P=0.031) while no differences were found for landing/pivoting (P=0.230). CONCLUSION: Knee bracing limited the excessive tibial rotation during pivoting under high loading activities in ACL-reconstructed knees with a hamstring graft. This partial restoration of normal kinematics may have a potential beneficial effect in patients recovering from ACL reconstruction with a hamstring autograft. LEVEL OF EVIDENCE: Level III, case-control therapeutic study.

Rupture of anterior cruciate ligament monitored by acoustic emission.

The scope of this study is to relate the acoustic emission (AE) during rupture of human soft tissue (anterior cruciate ligament, ACL) to the mechanisms leading to its failure. The cumulative AE activity highlights the onset of serious damage, while other parameters, show repeatable tendencies, being well correlated with the tissue's mechanical behavior. The frequency content of AE signals increases throughout the experiment, while other indices characterize between different modes of failure. Results of this preliminary study show that AE can shed light into the failure process of this tissue, and provide useful data on the ACL reconstruction.

Endurance markers are related with local neuromuscular response for the intact but not for the ACL reconstructed leg during high intensity running.

AIM: It has been demonstrated that the local neuromuscular response during high intensity exercise has a strong relationship with endurance markers. However, a diminished neuromuscular response has been reported for the operated leg in athletes having undergone anterior cruciate ligament reconstruction (ACLR). The purpose of the present study was to examine the relationships between endurance markers and the EMG response during high intensity running in ACLR athletes. METHODS: Fourteen ACLR soccer players underwent a GXT test to volitional exhaustion and a 10-min bout of high intensity running. During the 10-min bout, EMG data were recorded at the 3rd and 10th minute from the vastus lateralis bilaterally using a telemetric system. The final EMG levels were expressed as a percentage of the initial values. Pearson moment product correlations were used to assess the relationship between the endurance markers of VO2max, velocity at lactate threshold (vLT), velocity at 4mM (V4) and the final EMG levels. RESULTS: Final EMG levels for the intact leg had a very strong relationship with vLT (r=0.77, P=0.001) and a strong relationship with V4 (r=0.68, P=0.008). Final EMG levels for the reconstructed leg had moderate relationship with vLT (r=0.47, P=0.09) and V4 (r=0.52, P=0.06). CONCLUSION: The neuromuscular response of the intact leg during high intensity running shows strong to very strong relationships with endurance markers. Failure of the ACLR leg to present relationships of similar strength may indicate that chronic perturbations modify the ability of the local muscular environment to tolerate sustained high intensity efforts.

ACL injury and reconstruction: Clinical related in vivo biomechanics.

Several researchers including our group have shown that knee joint biomechanics are impaired after anterior cruciate ligament (ACL) injury, in terms of kinematics and neuromuscular control. Current ACL reconstruction techniques do not seem to fully restore these adaptations. Our research has demonstrated that after ACL reconstruction, excessive tibial rotation is still present in high-demanding activities that involve both anterior and rotational loading of the knee. These findings seem to persist regardless of the autograft selection for the ACL reconstruction. Our results also suggest an impairment of neuromuscular control after ACL reconstruction, although muscle strength may have been reinstated. These abnormal biomechanical patterns may lead to loading of cartilage areas, which are not commonly loaded in the healthy knee and longitudinally can lead to osteoarthritis. Muscle imbalance can also influence patients' optimal sports performance exposing them to increased possibility of knee re-injury. In this review, our recommendations point towards further experimental work with in vivo and in vitro studies, in order to assist in the development of new surgical procedures that could possibly replicate more closely the natural ACL anatomy and prevent future knee pathology.

Anterior cruciate ligament reconstruction with a quadrupled hamstrings tendon autograft does not restore tibial rotation to normative levels during landing from a jump and subsequent pivoting.

AIM: Recent research suggested that the anterior curciate ligament (ACL) reconstruction does not restore tibial rotation to normal levels when a bone patellar tendon bone (BPTB) graft is used during high demanding activities. Our goal was to determine if the usage of an alternative graft, as the quadrupled semitendinosus-gracilis (ST/G), restore tibial rotation to normal values in a population of athletically active individuals while performing a usual for their sport activity. METHODS: Eleven subjects, all reconstructed with an ST/G graft, were assessed in vivo, 9 months postoperatively, while they jumped off a 40 cm platform, landed on the ground and subsequently pivoted at 90 degrees. The evaluation period was identified from initial foot contact with the ground, included the pivoting of the ipsilateral leg, and was completed upon touchdown of the contralateral leg. By that time the patients had already returned to their sports activities. RESULTS: The maximum range of motion of the tibial rotation for the pivoting leg, during the evaluation period was found significantly (P=0.0001) larger in the reconstructed leg as compared to the intact contralateral, although both clinical and arthrometer assessments revealed restoration of anterior translation. CONCLUSIONS: It was concluded that ACL reconstruction with an ST/G graft does not restore tibial rotation to normal levels during this high demanding activity. It seems that new surgical techniques are needed to better replicate the actual anatomy and function of the natural ACL in order to address this problem.

Functional outcome after excision of heterotopic ossification about the knee in ICU patients.

The objective of this study was to evaluate the degree of improvement in the range of movement in the knee joint, sitting ability, and overall ambulation in patients with heterotopic ossification of the knee joint who underwent surgical excision of ectopic bone. Between 1999 and 2006, 14 patients (23 joints) with significant heterotopic ossification of the knee joint that required surgery were evaluated. We compared the range of movement in the knee joint, sitting ability, and overall ambulation in the preoperative and postoperative periods using the Fuller and Keenan classification systems. Range of movement increased in 82% of cases (19 knee joints). Sitting ability improved in 13 patients (93%). Postoperatively, ambulation in eight patients (57%) was remarkably superior. In conclusion, resection of heterotopic ossification may significantly improve the range of movement in the knee joint, sitting ability, and overall ambulation.

Electromechanical delay of the knee extensor muscles is not altered after harvesting the patellar tendon as a graft for ACL reconstruction: implications for sports performance.

Although the scar tissue, which heals the donor site defect, has different elasticity from the neighbouring patellar tissue, it remains unclear if this scar tissue can lead to the changes of the electromechanical delay (EMD) of the knee extensor muscles. If such changes do exist, they can possibly affect both the utilization of the stored energy in the series elastic component, as well as the optimal performance of the knee joint movement. The purpose of this study was to investigate the influence of harvesting the patellar tendon during anterior cruciate ligament (ACL) reconstruction and the associated patellar tendon scar tissue development on the EMD of the rectus femoris (RF) and vastus medialis (VM) muscles. Seventeen patients who underwent an ACL reconstruction using the medial third of the patellar tendon were divided in two groups based upon their post-operative time interval. Maximal voluntary contraction from the knee extensors, surface EMG activity, and ultrasonographic measurements of the patellar tendon cross-section area were obtained from both knees. Our results revealed that no significant changes for the maximal voluntary contraction of the knee extensors and for the EMD of the RF and the VM muscles due to patellar scar tissue development after harvesting the tendon for ACL reconstruction. The EMD, as a component of the stretch reflex, is important for the utilization of the stored energy in the series elastic component and thus, optimal sports performance. However, from our results, it can be implied that the ACL reconstruction using a patellar tendon graft would not impair sports performance as far as EMD is concerned.

The effects of anterior cruciate ligament reconstruction on tibial rotation during pivoting after descending stairs.

Recent in vitro research suggests that ACL reconstruction does not restore tibial rotation. This study investigated rotational knee joint stability in vivo during a combined descending and pivoting movement that applies a high rotational load to the knee joint. We studied 20 ACL reconstructed patients (bone-patellar tendon-bone graft) and 15 matched controls with a six-camera optoelectronic system performing the examined movement. In the control group the results showed no significant differences in the amount of tibial rotation between the two sides. No significant differences were also found between the contralateral intact leg of the ACL group and the healthy control. However, a significant difference was found within the ACL reconstructed group and between the reconstructed and the contralateral intact leg. Therefore ACL reconstruction may not restore tibial rotation even though anterior tibial translation has been reestablished.

The presence of proprioceptive mechanoreceptors in the remnants of the ruptured ACL as a possible source of re-innervation of the ACL autograft.

This study investigated the presence of neural mechanoreceptors in the remnants of the ruptured ACL as a possible source of reinnervation of the ACL autologous graft. The remainder of the torn ACL was selected for further histological investigation from 17 patients during ACL reconstruction 3 months to 3.5 years after injury. Perioperatively two types of ACL remnant were identified. Fifteen patients had portions of ACL adapted at the PCL. In all of these patients we found mechanoreceptors (I and II). In five patients we found mushroomlike remnants which included either none or small numbers of mechanoreceptors. Free neural ends were found in both patient groups. There was a significant difference between the groups in regard to the mean number of mechanoreceptors I and II per slice. In conclusion, in patients with an ACL remnant adapted to the PCL, mechanoreceptors exist even 3 years after injury. If we accept that restoration of proprioception is the result of reinnervation of the ACL, leaving the ACL remnants as a source, if this is surgically possible without risk of Cyclop's lesion, may be of potential benefit to the patient.

Alterations of the extensor apparatus after anterior cruciate ligament reconstruction using the medial third of the patellar tendon.

PURPOSE: The objective of this study was the ultrasound evaluation of the donor defect of the patellar tendon (PT) and the radiologic evaluation of the patella after harvesting of the medial third as a bone-patella tendon-bone (BPTB) graft for anterior cruciate ligament (ACL) reconstruction. TYPE OF STUDY: This was a cohort study. METHODS: In 45 patients who had ACL reconstruction, the extensor apparatus of the donor side was studied using ultrasound cross-sections and radiographs (anteroposterior, lateral, and a tangential view of the patella) 3 to 70 months postoperatively. Patients were divided into two groups. The early postoperative group (3 to 30 months postoperative) consisted of 27 patients (group A) and the late postoperative group (31 to 70 months postoperative) consisted of 18 patients (group B). The healthy contralateral extensor apparatus was used as control. RESULTS: In group A, the standard ultrasound cross-section area of the PT increased by 20.48%, whereas in group B, it decreased by 4.88%. In group A, the patellar height was decreased by 9.21% in the donor side compared with the control. In group B, the patellar height was decreased by 7.02%. In group A, the Merchant's congruence angle increased by 11.59 degrees, and for group B, this angle increased by 3.82 degrees. This finding indicated that, after the 30th postoperative month, lateral displacement of the patella was not statistically significant (P =.38). In addition, no significant differences were found in the lateral patellofemoral angle in either group. CONCLUSIONS: Our study indicates that the tendon defect is always healed and the final tendon cross-section area is 95% of the contralateral after the 30th postoperative month. In addition, there was a nonsignificant slight lateral displacement of the patella. In contrast, other studies found shown that there is a slight medial displacement of the PT after using the central third as a BPTB graft.

Patellar fractures associated with medial-third bone-patellar tendon-bone autograft ACL reconstruction.

Patella fractures following anterior cruciate ligament (ACL) reconstruction are a recognized but rarely reported complication. To our knowledge, 24 reports of patella fractures after ACL reconstruction using the central-third patella-tendon autograft have been reported in the literature. Patellar fractures associated with the use of the medial-third bone-patellar tendon-bone autograft have not been reported. This article describes four cases of patellar fractures in 478 ACL reconstructions between 1992 and 1999, using the medial third of the patellar tendon graft. All of them were transverse fractures of the patella but only one was displaced. All patients suffered local injury to the donor knee between 2 and 4 months postoperatively. No significant differences in the final outcome were noticed between the cases complicated with patellar fracture and those with uncomplicated ACL reconstructions.

Posterior cruciate ligament architecture: evaluation under microsurgical dissection.

PURPOSE: Our objective was to verify the fiber anatomy of the posterior cruciate ligament (PCL) and to measure the main dimensions and the femoral and tibial attachment site distances of the ligament after microsurgical dissection. We hypothesized that PCL anatomy is more complex than the 2 traditionally characterized bands. TYPE OF STUDY: This is a purely anatomic description of microdissections of the PCL, focused on the fine anatomy of the ligament. MATERIALS AND METHODS: Twenty-four fresh-frozen cadaveric knees were dissected using magnifying loupes and an operative microscope, being careful to avoid creating artificially separated bundles. The main dimensions of the PCL were measured using a micrometer. RESULTS: The anterior, central, posterior-longitudinal, and posterior-oblique were the 4 fiber regions identified based on their orientation and the osseous sites of their insertions. These were partially separable anatomically but were functionally distinct. The anterior and central fiber regions made up the bulk of the ligament, while the remaining 15% consisted of the posterior fiber regions. During manual joint motion, the behavior of these fiber regions was observed. The anterior fiber region appeared to be the most nonisometric and remained in tension mainly between 30 degrees and 90 degrees of flexion. The posterior fiber regions appeared to be the most isometric (especially the posterior-oblique) and remained in tension mainly in extension and partially in deep flexion. The central fiber region appeared to have an intermediate behavior and remained in tension mainly between 30 degrees and 120 degrees of flexion. Additionally, it appeared to be the widest of all fiber regions. CONCLUSIONS: These findings should be of interest and help in interpreting some of the anatomy encountered during arthroscopic examination of the PCL, both from the anterior and posterior lateral portals. Furthermore, this information should prove useful in selecting treatment for the PCL.

Nerve and vessel injuries during high tibial osteotomy combined with distal fibular osteotomy: a clinically relevant anatomic study.

Based on our clinical experience and an anatomical study, we examined the conditions under which injury to the popliteal artery, tibial nerve or peroneal nerve and its branches may occur during high tibial osteotomy. In 250 high tibial osteotomies performed in our department, we observed the following intraoperative complications. (1) The popliteal artery was severed in 1 patient and repaired by the same surgical team using a microsurgical technique. (2) A tibial nerve paresis also occurred in 1 patient. (3) In 3 patients, temporary palsy of the anterior tibialis muscle was documented. (4) In 4 other patients, palsy of the extensor hallucis longus occurred. To investigate the causes of these complications in the popliteal artery, tibial nerve and branches of the peroneal nerve, we dissected the neurovascular structures surrounding the area of the osteotomy in 10 cadaveric knees and performed a high tibial osteotomy in another 13 cadaveric knees. We concluded the following. (1) The popliteal artery and tibial nerve are protected, at the level of the osteotomy, behind the popliteus and tibialis posterior muscles. Damage can occur only by placing the Hohman retractor behind the muscles. The insertion of the muscles is very close to the periosteum and can be separated only with a scalpel. (2) The tibialis anterior muscle is innervated by a group of branches arising from the deep branch of the peroneal nerve. In two-thirds of the dissected knees, we found a main branch close to the periosteum, which can be damaged by dividing the muscle improperly or due to improper placement and pressure of the Hohman retractor. This may explain the partially reversible muscle palsy. (3) The extensor hallucis longus is also innervated by 2-3 thin branches, arising from the deep branch of the peroneal nerve, but in 25% of the specimens, only one large branch was found. This branch is placed under tension by manipulating the distal tibia forward. Thus, it may be damaged by the Hohman retractor during distal screw fixation, tensioned by hyperextension or directly injured during midshaft fibular osteotomy.

Difficulties and early results of the endoscopic carpal tunnel release using the modified Chow technique.

In reporting on the preliminary results of our series of 76 patients, this paper aims to identify potentially complicating aspects of endoscopic carpal tunnel release (ECTR) using the two-portal Chow technique, and to recommended solutions, based on our early experience, which enhance the ease and safety of this minimally invasive technique. Of the first 24 patients, 16 cases required conversion to an open procedure. Based on these initial cases, we developed certain modifications of the Chow technique which precluded any need for open conversion in the 60 remaining cases. During a follow-up interval ranging from 4 to 24 months, there was no recurrence of carpal tunnel symptoms, and the average time to resumption of work activity was 14 days. The complication rate was 5% and included one case of transient hypesthesia, one case of extended hematoma, and one hypersensitive scar. All complications resolved at subsequent follow-up. In our experience, correct positioning of the hand, proper injection of local anesthetic, use of magnifying loupes, and correct use of instruments are essential for a safe and successful procedure.

Anterior cruciate ligament reconstruction with the press-fit technique. 2-5 years followed-up of 42 patients.

42 patients underwent anterior cruciate ligament (ACL) reconstruction with the press-fit technique. The ACL was reconstructed with a bone-tendon-bone graft from the medial third of the patellar tendon. The graft was stabilized without screws in the femur and tibia by press-fit. To imitate the anatomical functioning of the ACL, the femoral bone block was placed with the tendon close to the over-the-top position. The tibial block was then placed in a trough on the tibia, so that the ligament fibres were parallel and tight during extension and slightly inverted during flexion. At evaluation mean 41 (25-61) months postoperatively, the mean Lysholm score was 93 (80-100) points, the mean activity level was 6 (3-10) points, and the mean translation of the tibia head, measured by the KT-1000 arthrometer (side-to-side difference), was 2 (0-7) mm. Only 3 of the patients suffered loss of extension (5 degrees). Patients who underwent reconstruction at least 4 months after the injury had better results than those who were operated earlier. The press-fit method allowed for anatomic substitution of the ACL with a stable graft without the disadvantages associated with screws. This method gave early postoperative functioning of the knee and good mid-term results.

Application of silicon tissue expanders for the direct or indirect coverage of soft tissue defects in the extremities.

In a 2 year prospective study, 17 tissue expanders were placed on the extremities of 17 patients. The aim was to cover soft tissue defects in the forearm of 8 patients after chinese flap dissection, which was used either as a free or reversed flap. In 8 of the remaining patients, the expanded skin was placed directly on the affected region as a local fasciocutaneous flap. In 1 patient it was determined intra-operatively that the prepared extended skin was not necessary to treat the patient. The tissue expander was successfully used to cover skin defects, both directly and indirectly, in the lower extremity (7 cases) and in the upper extremity (9 cases). Neither infection nor necrosis was observed in the flaps and the cosmetic results, particularly in the forearm, were satisfactory.

Osteoid osteoma in the differential diagnosis of persistent joint pain.

We report 20 cases (13 male and 7 female), mean age 21 years) of juxta-articular osteoid osteoma. The distribution of affected joints was as follows: hip joint (7 cases), knee joint (2 cases), ankle joint (2 cases); iliosacral joint (2 cases), lumbar spine (2 cases), carpus (2 cases), shoulder (1 case), second metacarpal (MCP; 1 case) and first metatarsal (MTP; 1 case). The duration between the onset of symptoms and diagnosis varied from 8 months to approximately 4 years. In juxta-articular osteoid osteoma, the clinical picture and the radiographic findings are often atypical, and this may lead to misdiagnosis and delayed definitive treatment. In young patients with persistent undiagnosed pain, the possibility of an osteoid osteoma should be considered. When the clinical picture is suggestive but radiological findings are negative, we must proceed to further investigation with bone scintigraphy and computed tomography. These examinations should be repeated 1 year after the onset of symptoms because initially negative findings may become positive at a later date. When the diagnosis of an osteoid osteoma is confirmed, surgical excision leads to complete relief of the symptoms.

Transpositional microsurgery in multiple digital amputations.

In 34 of the 62 patients treated for complete multiple digital amputations, the severed part was not replanted in its anatomical position, but in the place of the most useful stump. This procedure is defined as transpositional digital microsurgery and refers to the transposition and replantation of any digit to another stump which plays a more significant role in the function of the hand. Twenty-eight patients had transposition of a digit, while six patients underwent thumb transposition. All except six of the transposed digits survived, while all of the thumbs survived the surgical procedure. The cosmetic appearance of the hand with a transposed digit or thumb was acceptable to the patients. Two-point discrimination was assessed to be 10-14 mm for the transposed digits, and the functional ability of the transplanted digit was comparable to digits which were replanted in their anatomical position. In conclusion, transpositional digital microsurgery remains a useful alternative for the treatment of multiple digit amputations, particularly in patients with severely damaged non-replantable amputated parts.

Vascularised bone grafts in the treatment of long bone defects.

Reconstruction of large bony defects of long bones was performed using vascularised fibular grafts in four patients at the Department of Orthopaedic Surgery of the University of Ioannina Medical School. Indications for grafting procedures in this small series had been the loss of bone due to the extensive resection of avascular and necrotic bone from septic pseudoarthrosis in three patients and congenital pseudarthrosis secondary to neurofibromatosis in a child. Primary skeletal union with graft hypertrophy occurred in three of the patients. The fourth patient had an asymptomatic nonunion at the proximal end of the graft. The result in each patient was the presence of a well-aligned limb that had normal or nearly normal motion and acceptable length.