Purpose

There are concerns with regard to the physiological effects of reamed intramedullary femoral fracture stabilisation in patients who have received a pulmonary injury. This large animal study used invasive monitoring techniques to obtain sensitive cardiopulmonary measurements and compared the responses to Early Total Care (reamed intramedullary femoral fracture fixation) to Damage Control Orthopaedics (external fixation), after the induction of acute lung injury. We hypothesised a greater cardiopulmonary response to intramedullary fracture fixation.

Low back pain (LBP) in the region of the lumbar spine is a significant problem among individuals, and efforts focused on treating both the symptoms and causes of LBP have proven to be difficult. Aside from conservative treatments, the predominant surgical approach for treating degenerative spine conditions has been to fuse the vertebral bodies at the symptomatic level. Even today, surgical fusion and its effect on adjacent levels are still not fully understood. Therefore, the objective of this study was to use fluoroscopy and mathematical modeling techniques to identify the in vivo kinematics and kinetics in subjects having either a normal, degenerative or fused condition of the lumbar spine.

Twenty-five subjects (ten normal, ten degenerative, and five fusion) were evaluated under fluoroscopic surveillance while performing flexion/extension of the lumbar spine. Subjects within the normal and degenerative groups were analyzed only once, while subjects from the fusion group were analyzed both pre-operatively and at a minimum of six months post-operative. The fusion group consisted of three subjects symptomatic at L4/L5, with the remaining two subjects symptomatic at L5/S1. In vivo kinematics data were derived using a 3D-to-2D model fitting algorithm and served as input into a 3D mathematical model of the lumbar spine. The parametric, inverse dynamics mathematical model was created to allow for the determination of the bearing surface contact and muscle forces at each level of the lumbar spine.

Three-dimensional kinematics analyses revealed that subjects classified as having a normal lumbar spine experienced a more uniform motion pattern compared to those observed in the degenerative and fusion groups. Alternatively, the degenerative and fusion subjects demonstrated a more coupled motion pattern in order to perform in plane flexion/extension. Compared to the normal group, rotations in the sagital plane decreased by an average of 28% at the pathological level in the degenerative group, while in the fusion group segmental motions slightly increased at the adjacent levels. Results from the mathematical model also revealed higher out-of-plane forces and increased loading at symptomatic and adjacent levels in both the degenerative and fused groups compared to forces observed in the normal spine.

The abnormal motion patterns, which result from decreased or loss of motion at pathological levels in the degenerative and fusion groups, are believed to result in higher resultant forces in the spine. This may be subjecting the intervertebral discs to increased stresses, and as a consequence may be linked to more rapid degeneration at levels where the abnormal kinematics are occurring.

Aims: There are concerns over the physiological effects of intramedullary femoral fracture stabilisation in patients with pulmonary injury. This large animal study used invasive monitoring to obtain sensitive cardiopulmonary measurements and compared the responses of ‘Early Total Care’ (intramedullary fracture fixation) and ‘Damage Control’ (external fixation), after the induction of lung injury.

Methods: Acute lung injury (PaO2/FiO2 < 200 mmHg) was induced in 12 invasively monitored and terminally anaesthetised sheep via oleic acid infusion into the right atrium. Each animal underwent surgical femoral osteotomy and fixation with either reamed intramedullary (n=6) or external fixation (n=6). Haemodynamic and arterial blood-gas measurements were recorded at baseline, 5, 30 and 60 minutes after fracture stabilisation.

Results: The mean (+/− S.E.) PaO2/FiO2 fell significantly (p< 0.05) from 401 (+/− 39) to 103 (+/− 35) and 425 (+/− 27) to 122 (+/− 21) in the externally fixated and intramedullary nailed groups respectively after acute lung injury. The further combined effect of surgical osteotomy and fracture fixation produced a mean (+/− S.E.) PaO2/FiO2 of 98 (+/− 21) and 114 (+/− 18), in the externally fixated and intramedullary nailed groups immediately after surgery. This was not significantly different within or between groups. Similarly the pulmonary vascular resistance (PVR) measured at 5.8 (+/− 0.8) and 4.8 (+/− 0.7) after lung injury in the externally fixated and intramedullary nailed groups changed to 5.7 (+/− 0.5) and 4.0 (+/− 0.7) after surgical osteotomy and fracture fixation (no significant difference within or between groups). The PaO2/FiO2 or PVR was not significantly different at the monitored 5, 30 and 60 minute intervals after fracture stabilisation.

Conclusion: Against a background of standardised acute lung injury, there was no further deterioration produced by the method of isolated femoral fracture fixation in sensitive physiological parameters commonly used during intensive care monitoring.

Purpose of Study: To further study a group of patients with characteristic features presenting with significant, perisistent, and seemingly hard to diagnose and so treat, knee pain.

Methods/Results: 16 cases were collected. The was no association with age. 8 cases were sent as a second opinion.

Causation: 7 cases:direct trauma [5: associated with MCL tears (1 chronic overload from triple-jump),1:a blow to front of knee, 1:chronic from kneeling]

In all cases the time to make the diagnosis was prolonged. All had pain, which on close questioning was ‘neuritic’ [burning] in approximately 2/3. It was exceedingly well localized in all. Altered sensation in the appropriate distribution was noted by the patient in 3 cases, but shown in 5 cases on examination. A positive Tinel test was present in all cases.

In approximately half of cases ultrasound plus diagnostic injection of local anaesthetic [+/− steroid] was useful. However 15 of the 16 came to surgery in which a neurolysis or removal of neuroma, in 3 cases, [all confirmed on histology] was undertaken plus the underlying causative factor dealt with eg excision of osteophyte or scar. One case settled [90% better according to patient] after ultrasound-guided injection of a prepatellar bursa which was irritating the infrapatellar branch of the nerve. Of the 15 who had had surgery 12 had complete resolution of symptoms.

Conclusion: Although a relatively uncommon this scenario is worth considering as a cause of significant morbidity, with a good outcome from treatment in most cases. The presentation is of persistent very well localized troubling pain with marked tenderness, and a positive Tinel test.