مجله جراحی استخوان و مفاصل ایران
سال سیزدهم شماره 2 (پیاپی 51، بهار 1394)

Rupture of the anterior cruciate ligament (ACL) is the most common knee injury during sport activities. The purpose of this study was to investigate the results of ACL reconstruction using middle 1/3 of the autologous patellar ligament by miniarthrotomy approach in young patients.
In a descriptive study, 57 patients (55 male, 2 female) at age of 20 to 45 years old, who were referred with ACL rupture and treated with ACL reconstruction using autograft bone-patellar-bone during a 2-year period in a training hospital in Ahvaz, Iran, were studied. The clinical results were investigated with an 11.7 months (7-28 months) follow-up, using Lysholm Knee Score, and physical re-evaluation.
In 33 cases, right knee and in 24 left knee was affected. Eighty-six percent of the patients had no limitation in knee motion after surgery, and 82 percent had no knee instability. Ninety-six percent of the patients could return to the pre-injury sport activity. The mean Lysholm knee score was 83.63 (69-93).
Reconstruction of the anterior cruciate ligament using autograft bone-patellar-tendon with miniarthrotomy has clinically acceptable results.

Wrong placement of the ACL transplant especially in femoral site can result in early graft failure. Anatomical placement of the femoral tunnel results in restoration of knee kinematics closer to those of the intact knee. This placement could be performed by either using “aimer device” or with “free hand” methods. We compare the geometric position of femoral canal created by these two techniques.
In a prospective study, 22 patients were devided into two groups (11 patients) and operated by using femoral aimer instrument and “Free hand” techniques. Intra-operative fluoroscopy for femoral guide pin position was performed to determine the guide pin position. Vertical and horizontal coordinates of guide pins in both groups were outlined and compared with standard anatomical point of guide pins.
in “aimer” group the coordinates of the guide pin location was 41.33% vertically and 33.49% horizontally and the difference with anatomic location in both vertical (p=.03) and horizontal (p=.02) vectors was significant. The coordinates for the location of the guide pin in the “free hand” group were 35.33% and 33.07% respectively and the difference between anatomical location and guide pin width was significant (p=.04), and in this group, difference in the height was observed. The sum errors in width and height plane in “aimer” and “free hand” groups were 13.82 and 7.4 respectively.
Anatomic positioning of guide pin is possible through both free hand and instrument techniques. The percentage of error in instrument technique is more than free hand method.

Anterior cruciate ligament (ACL) is a critical element in the biomechanics of knee joint stability. ACL tear increases the risk of meniscal and articular cartilage injury. This study evaluated the occurrence of meniscal and chondral injuries and the results of ACL reconstruction with more than 7 years delay in ACL reconstruction.
In a cross sectional study, 43 patients (39 men, 4 women) at mean age of 38 years, who underwent ACL reconstruction with a delay of more than 7 years, were studied. The Lysholm, IKDC, Tenger and KOOS scores were evaluated before surgery and at the last follow up. The observed meniscal or chondral lesions were collected from the patients’ arthroscopic records. The mean follow-up was 34 months.
The mean time interval between primary trauma and ACL reconstruction surgery was 121 months. A total of 39 cases (90/7%) had chondral lesions which include 20 cases of grade I/II and 19 cases of grade III/IV lesions. In 35 patients (81.4%) meniscal tear was observed. Only two cases (4.6%) had isolated ACL tear. A statistically significant improvement in IKDC, Lysholm, KOOS, and Tegner score was observed following surgical treatment (p Longstanding ACL tear leads to increase the occurrence of meniscal and cartilage injuries. Delayed ACL reconstruction in this group of patients can improve IKDC, Lysholm and KOOS knee scores and Tegner activity level.

High tibial osteotomy (HTO) is a common surgical procedure for treatment of patients with varus malalignment. The success rate of the procedure is strongly dependent on the quality of correction. The purpose of this study was to simulate the HTO in a patient with varus deformity in order to explore the interactions between the wedge angle, the mechanical axis, and the knee joint configuration.
A finite-element model of the knee joint of a patient with varus deformity was developed. The geometry was obtained using the whole limb CT scans and the knee MR images. The bones were assumed as rigid bodies, the articular cartilage and the meniscus as elastic solids, and the ligaments as nonlinear springs. A 600N force was applied at the femoral head in the line of the mechanical axis and the resulting knee configuration was investigated. The HTO was simulated by insertion of wedges with different angles beneath the tibial plateau and application of the resulting alteration of the loading axis in the model.
The results indicated that the actual change of the mechanical axes was always smaller than was predicted by a geometric pre-planning approach that does not consider the effect of soft tissue on the post-operative configuration of the knee joint.
It was suggested that subject-specific models can improve the results of the HTO by simulating the operation before surgery and determining the optimal wedge angle that locates the mechanical axis in the middle of the knee.

Knee arthroplasty has been traditionally based on mechanical alignment restoration. In the newer, “Kinematically aligned knee replacement”, the eroded bone and joint surfaces in addition to saw-blade thickness are removed and replaced by the components. This study compared the results of two techniques of knee arthroplasty.
In a clinical trial study, 90 patients who were candidates for knee arthroplasty were divided into 2 groups: 45 cases received knee arthroplasty by “mechanically aligned” and 45 by “Kinematically aligned” technique. The two groups were compared after 1 year by Lysholm score, hospitalization period, subjective satisfaction, and period of need for ambulatory aid.
73 patients referred for follow up: 37 patients in the kinematic and 36 in the mechanical group. The mean hemoglobin drop was not significantly different between the two kinematic and mechanical groups; while the post operation mean hemoglobin drop difference was significant (p=.001). No significant difference in the patient satisfaction of the operation was observed between two groups. The difference of mean Lyshlom score was different between two groups (p=.000).
kinematically aligned” knee replacement is associated with less pain, earlier return to daily activity, lesser intra operative bleeding and more patient satisfaction.

Total hip arthroplasty (THA) is the replacement of the hip joint by artificial prosthesis. This surgery is one of the most successful orthopaedic surgeries. The most important challenge to the THA is bearing surface of these implants, which is closely related to the survival of the prosthesis. Following the introduction of the first successful implant in THA, there has been great progress in implant production, by increasing the power and reducing the friability and wear of the bearing surfaces. The wear particles can remain in the host tissue, generate osteolysis and reduce the implant survival. These problems with bearing surfaces have led to creation of other bearing surfaces such as metal-on-polyethylene, metal-on-metal, ceramic-on-ceramic and ceramic-on-polyethylene with improved characteristics. Such types of implants can be used for young and more active patient, in addition to the elderly who is less active. In the present review, the different type of bearing surfaces with their advantages and disadvantages has been discussed.

Proceedings of the Internatoinal Consensus Meeting on Periprosthetic Joint Infection
Chairmen: Javad Parvizi MD, FRCS; Thorsten Gehrke, MD
Eighth Section: Operative Environment