Introduction. Metabolic bone disease encompasses disorders of bone mineralization, abnormal matrix formation or deposition and alteration in osteoblastic and osteoclastic activity. In the paediatric cohort, patients with metabolic bone disease present with pain, fractures and deformities. The aim was to evaluate the use of lateral entry rigid intramedullary nailing in lower limbs in children and adolescents. Materials and Methods. Retrospective review was performed for an 11-year period. Lower limb rigid intramedullary nailing was performed in 27 patients with a total of 63 segments (57 femora, 6 tibiae). Majority of patients had underlying diagnoses of osteogenesis imperfecta or fibrous dysplasia (including McCune Albright disease). Mean age at surgery was 14 years. Indications for surgery included acute fractures, prophylactic stabilisation, previous nonunion and malunion, deformity correction and lengthening via distraction osteogenesis. Results. All fractures healed. Correction of deformity was successfully achieved in all segments. Delayed union occurred in 4 segments in 1 patient and was successfully treated with nail dynamization. Other complications included prominence, cortical penetrance and loosening of locking screws. One patient who had lengthening performed had nonunion and was managed with exchange nailing and adjunctive measures. Conclusions. Rigid intramedullary nailing is very effective in stabilisation and deformity correction of long bones in adolescent patients with pathological bone disease. The technique has low complication rates. We recommend the use of this technique in paediatric units with experience in managing metabolic bone conditions

Aims

The preventive effects of bisphosphonates on articular cartilage in non-arthritic joints are unclear. This study aimed to investigate the effects of oral bisphosphonates on the rate of joint space narrowing in the non-arthritic hip.

Osteoarthritis (OA) is a highly prevalent degenerative joint disorder characterized by joint pain and physical disability. Aberrant subchondral bone induces pathological changes and is a major source of pain in OA. In the subchondral bone, which is highly innervated, nerves have dual roles in pain sensation and bone homeostasis regulation. The interaction between peripheral nerves and target cells in the subchondral bone, and the interplay between the sensory and sympathetic nervous systems, allow peripheral nerves to regulate subchondral bone homeostasis. Alterations in peripheral innervation and local transmitters are closely related to changes in nociception and subchondral bone homeostasis, and affect the progression of OA. Recent literature has substantially expanded our understanding of the physiological and pathological distribution and function of specific subtypes of neurones in bone. This review summarizes the types and distribution of nerves detected in the tibial subchondral bone, their cellular and molecular interactions with bone cells that regulate subchondral bone homeostasis, and their role in OA pain. A comprehensive understanding and further investigation of the functions of peripheral innervation in the subchondral bone will help to develop novel therapeutic approaches to effectively prevent OA, and alleviate OA pain.

Cite this article: Bone Joint Res 2022;11(7):439–452.

CT-based three-dimensional (3D) pre-operative imaging along with 2D orthogonal sections defined by the plane of the scapula (axial, sagittal and coronal planes) has been demonstrated by many research groups to be a very accurate way to define the bone pathology and alignment/subluxation of the humeral head in relationship to the center line of the scapula or the center of the glenoid fossa. When 3D CT imaging is combined with 3D implant templating the surgeon is best able to define the optimal implant and its location for the desired correction of the bone abnormalities. The use and value of 3D imaging is best when the there is more severe bone pathology and deformity. Transferring the computer-based information of implant location to the surgical site can involve multiple methods. The three methods discussed in the literature to date including use of standard instrumentation in a manner specified by the pre-operative planning, use of single-use patient specific instrumentation and use of reusable patient specific instrumentation. Several cadaver and sawbone studies have demonstrated significant improvement in placement of the glenoid implant with both single use and reusable patient specific instrumentation when compared to use of 2D imaging and standard instrumentation. Randomised clinical trials have also shown that 3D planning and implant templating is very effective in accurate placement of the implant in the desired location using all three types of instrumentation. The optimal use of this technology is dependent upon the severity of the pathology and the experience and preference of the surgeon. With more severe pathology and less surgeon experience 3D pre-operative imaging and templating and use of some level of patient specific instrumentation provides more accurate placement of the glenoid implant

Aims

To investigate whether idiopathic osteonecrosis of the femoral head (ONFH) is related to impaired osteoblast activities.

INTRODUCTION:. Previous modalities such as static x-rays, MRI scans, CT scans and fluoroscopy have been used to diagnosis both soft-tissue clinical conditions and bone abnormalities. Each of these diagnostic tools has definite strengths, but each has significant weaknesses. The objective of this study is to introduce two new diagnostic, ultrasound and sound/vibration sensing, techniques that could be utilized by orthopaedic surgeons to diagnose injuries, defects and other clinical conditions that may not be detected using the previous mentioned modalities. METHODS:. A new technique has been developed using ultrasound to create three-dimensional (3D) bones and soft-tissues at the articulating surfaces and ligaments and muscles across the articulating joints (Figure 1). Using an ultrasound scan, radio frequency (RF) data is captured and prepared for processing. A statistical signal model is then used for bone detection and bone echo selection. Noise is then removed from the signal to derive the true signal required for further analysis. This process allows for a contour to be derived for the rigid body of questions, leading to a 3D recovery of the bone. Further signal processing is conducted to recover the cartilage and other soft-tissues surrounding the region of interest. A sound sensor has also been developed that allows for the capture of raw signals separated into vibration and sound (Figure 2). A filtering process is utilized to remove the noise and then further analysis allows for the true signal to be analyzed, correlating vibrational signals and sound to specific clinical conditions. RESULTS:. Numerous tests have been conducted using this ultrasound technique to create 3D bones compared more traditional techniques, MRI and CT Scans. These tests have shown repeatedly that 3D bones can be created with an error less than 1.0 mm. Soft-tissues at the joint of question are also created with a high accuracy. Sound signals have been analyzed and correlated to specific knee and hip clinical pathology as well as complications after Total Joint Arthroplasty. Sounds such as squeaking, knocking, grinding, clicking and even a rusty door hinge have been recovered during weight-bearing activities. DISCUSSION:. Both CT scans and x-rays emit radiation, and static CT scans and MRI scans are conducted under non weight-bearing conditions. These two new orthopaedic diagnostic techniques, ultrasound and sound, allow a surgeon to make clinical diagnoses while the patient is performing weight-bearing, dynamic activities, while not being subjected to harmful radiation. Sound analyses allow for support of the ultrasound and physical exam that can lead to enhanced diagnostics that are not possible using only a visual based analysis. Early results are promising for both of these new diagnostic techniques. This study revealed that weight-bearing, dynamic diagnoses can be made by an orthopaedic surgeon and could have distinct advantages compared to traditional techniques

Posterior segmental fixation of the cervical spine facilitates fixation in sub-optimal bone, abnormal anatomy, and complex deformity. Compared to lateral mass plates a screw rod construct provides a stable construct in osteoporotic bone or in cases where the lateral masses are fractured or missing. To investigate whether a posterior cervical screw- rod construct is an effective, stable and safe means of posterior cervical fixation. Retrospective evaluation of consecutive patients undergoing a posterior cervical stabilization with a screw- rod construct with clinical and radiographic evaluation. Clinical variables included age, gender, neurologic status, surgical indication, number of levels stabilized, and number of screws. Note was made as to whether a laminectomy was performed and concomitant anterior surgery. Clinical and radiographic assessments were carried out immediately after surgery and at six weeks, three, six, twelve months and annually after surgery. Eighty-three patients had five hundred and seventy-three screws placed from October 1998 to December 2003. Mean patient age was fifty-seven. Mean follow-up was twenty-three months, (one to sixty months). The underlying diagnoses were inflammatory arthritis thirty-three, spondylotic myelopathy twenty-nine and trauma in twenty-one patients. Forty-four patients (53% had motor deficit, forty-seven patients (57%) had sensory deficit. Fixation was carried out over an average of five levels (range – two to eight). Mean number of screws per construct was seven (range – four to fourteen). The instrumentation was successfully implanted in all despite lateral mass deficiencies (fracture, poor bone) and coronal and sagittal plane deformities. Late occipital fixation failure was encountered in one patient. There was no loss of alignment or surgical correction on follow-up radiographs. A posterior screw-rod system allows for treatment of traumatic and degenerative and inflammatory conditions. Crossing the occipitocervical or cervicothoracic junctions is easily afforded. We have had excellent success without complications from screw placement or pseudoarthrosis

It is well appreciated that thigh pain following recent arthroplasty surgery is likely to be due to prosthetic loosening or infection. Both these sequelae can lead to periprosthetic fracture presenting complex challenges to even experienced surgeons. Revision arthroplasty patients are prone to both fatigue and insufficiency fractures as they may have reduced bone stock after previous surgery and reduced bone density secondary to medical and immobility reasons. The post operative painfree condition will frequently permit early load bearing leading to a relatively rapid increase in activity and load bearing. Fatigue fractures occur in bone of normal quality subject to abnormal cyclical overloading, leading to resorption and eventual failure, before adequate time has passed to permit adaptive remodelling. Insufficiency fractures occur when normal physiological loads are applied to bone of abnormal quality. Surprisingly few periprosthetic stress fractures are reported in the literature but a series notes lateral tensile stress fractures associated with varus prosthetic alignment. These all occurred near the tip of the prosthesis. The case of an unusual Gruen Zone 2, Vancouver B1 stress fracture, 9 months following revision arthroplasty is reported. Initially loosening was suspected due to the development of load bearing thigh pain. Plain radiography revealed the development of a dreaded black line, consistent with a stress fracture. Bone scintigraphy revealed the typical appearance of a stress fracture in the absence of loosening or infection. The unusual location of this stress fracture allowed consideration of conservative non weight bearing management which lead to the alleviation of symptoms rather than further revision surgery. This report illustrates this unusual stress fracture and highlights the importance of careful loading practises to permit adequate remodelling following complex revision surgery

Objectives

Little is known about tissue changes underlying bone marrow lesions (BMLs) in non-weight-bearing joints with osteoarthritis (OA). Our aim was to characterize BMLs in OA of the hand using dynamic histomorphometry. We therefore quantified bone turnover and angiogenesis in subchondral bone at the base of the thumb, and compared the findings with control bone from hip OA.

Increased incidence of complications has been reported when lengthening limbs with underlying bone disorders such as dysplasias and metabolic bone diseases. There is a paucity of literature on limb lengthening in Osteogenesis Imperfecta (OI), probably due to the concern that the bone containing abnormal collagen may not tolerate the external fixators for a long term and there may not be adequate regenerate formation from this abnormal bone. We performed limb lengthening and deformity correction of nine lower limb long bones in six children with OI. Four children were type I and two were type IV OI as per Sillence classification. The mean age was 14.7 years. All six children had lengthening for femoral shortening and three of them also had lengthening for tibial shortening on the same side. Angular deformities were corrected during lengthening. Five limb segments were treated using a monolateral external fixator and four limb segments were treated using an Ilizarov external fixator. In three children, previously inserted femoral intramedullary nails were left in situ during the course of femoral lengthening. The average lengthening achieved was 6.26 cm. Limb length discrepancies were corrected to within 1.5 cm of the length of the contralateral limb in five children. In one child with fixed pelvic obliquity and spinal scoliosis, functional leg length was achieved. The mean healing index was 33.25 days/cm of lengthening. Among the complications significant ones included, one deep infection, one fracture through the midshaft of the femur, and development of anterior angulation deformity after the removal of the fixator in one tibia. Abnormal bone of OI tolerated the external fixator throughout the period of lengthening without any incidence of migration of wires and screws through the soft bone when distraction forces were applied. The regenerate bone formed within the time that is normally expected in limb lengthening procedures performed for other conditions. We conclude that despite abnormal bone characteristics, limb reconstruction to correct limb length discrepancy and angular deformity can be done safely in children with OI

Objectives

An important measure for the diagnosis and monitoring of knee osteoarthritis is the minimum joint space width (mJSW). This requires accurate alignment of the x-ray beam with the tibial plateau, which may not be accomplished in practice. We investigate the feasibility of a new mJSW measurement method from stereo radiographs using 3D statistical shape models (SSM) and evaluate its sensitivity to changes in the mJSW and its robustness to variations in patient positioning and bone geometry.